nsIDOMDesktopNotificationCenter
the nsidomdesktopnotificationcenter interface implements the dom navigator.moznotification interface.

Basic Concepts of Multicol - CSS: Cascading Style Sheets
key concepts and terminology multicol is unlike any of the other layout methods we have in css in that it fragments the content, including all descendent elements, into columns.

Digital audio concepts - Web media technologies
audio file size and network bandwidth once you know the size of a single audio frame and how many frames per second make up your audio data, you can easily calculate how much space the raw sound data itself will occupy (and therefore how much bandwidth it would consume on a network).

Index - Web APIs
68 animation.finished api, animation, experimental, property, reference, web animations, finished, web animations api the animation.finished read-only property of the web animations api returns a promise which resolves once the animation has finished playing.
...once put into an audiobuffer, the audio can then be played by being passed into an audiobuffersourcenode.
... 488 cssunparsedvalue.foreach() api, css typed object model api, cssunparsedvalue, constructor, experimental, houdini, method, needsexample, reference, foreach() the cssunparsedvalue.foreach() method executes a provided function once for each element of the cssunparsedvalue.
...And 67 more matches

Index - Learn web development
3 accessible multimedia accessibility, article, audio, beginner, codingscripting, html, images, javascript, learn, multimedia, video, captions, subtitles, text tracks this chapter has provided a summary of accessibility concerns for multimedia content, along with some practical solutions.
... beginner, infrastructure, navigation, needsactivelearning hyperlinks, usually called links, are a foundational concept behind the web.
... beginner, infrastructure, needsactivelearning, url, resources, urls with hypertext and http, url is one of the key concepts of the web.
...And 23 more matches

Index - Archive of obsolete content
once the content has been downloaded, the extension authors proceed to use eval() to decode the string content into javascript objects.
... 456 layout system overview gecko layout is primarily concerned with providing a presentation to an html or xml document.
...once installed, it will gather startup data and display it in the about:startup page.
...And 14 more matches

DevTools API - Firefox Developer Tools
return value: a promise that is fulfilled with the toolbox instance once it has been initialized and the selected tool is loaded.
... return value: a promise that is fulfilled once the toolbox has been destroyed.
... return value: a promise that is fulfilled with the toolpanel object once the tool has finished loading.
...And 14 more matches

Rendering and the WebXR frame animation callback - Web APIs
once your webxr environment has been set up and an xrsession created to represent an ongoing xr environment session, you need to provide frames of the scene to the xr device for rendering.
... preparing the renderer once the xr session has been set up, with the webgl framebuffer connected and webgl primed with the data it needs in order to render the scene, you can set up the renderer to start running.
...once that's in hand, you request that the browser call your rendering function the next time it needs a framebuffer to render your scene.
...And 14 more matches

Index
once you have imported certificates and keys into the nss database, you can easily look them up and use them again.
...nss will usually create an in-memory (ram) presentation of certificates, once a certificate has been received from the network, read from disk, or looked up from the database, and prepare in-memory data structures that contain the certificate's properties, as well as providing a handle for the programmer to use.
... once the application is done with a handle, it should be released, allowing nss to free the associated resources.
...And 11 more matches

Index
this document attempts to help them do so, first by explaining the underlying concepts, and second by describing a number of common javascript patterns that cause leaks.
...the book is presented as a tutorial about creating xpcom components, but it covers all major aspects, concepts, and terminology of the xpcom component model along the way.
... 164 iaccessiblecomponent interfaces, xpcom, xpcom interface reference this interface provides the standard mechanism for an assistive technology to retrieve information concerning the graphical representation of an object.
...And 10 more matches

sslfnc.html
nss_init isnot idempotent, so call it only once.
...nss_initreadwrite isnot idempotent, so call it only once.
... nss_nodb_init isnot idempotent, so call it only once.
...And 9 more matches

Using IndexedDB - Web APIs
if you are not familiar with indexeddb, you should first read basic concepts about indexeddb.
... with these big concepts under our belts, we can get to more concrete stuff.
...once it is fired, the onsuccess() function on request is triggered with the success event as its argument.
...And 9 more matches

CSP: script-src - HTTP
'nonce-<base64-value>' an allow-list for specific inline scripts using a cryptographic nonce (number used once).
... the server must generate a unique nonce value each time it transmits a policy.
... it is critical to provide an unguessable nonce, as bypassing a resource’s policy is otherwise trivial.
...And 8 more matches

Layout System Overview - Archive of obsolete content
layout's job: provide the presentation layout is primarily concerned with providing a presentation to an html or xml document.
...layout's support for aural presentations is undeveloped, though conceptually, it is possible and supported by the architecture.
... how layout does its job: frames and reflow so, layout is concerned with providing a presentation, in galley or paged mode.
...And 7 more matches

Cooperative asynchronous JavaScript: Timeouts and intervals - Learn web development
these functions are: settimeout() execute a specified block of code once after a specified time has elapsed.
... settimeout() as we said before, settimeout() executes a particular block of code once after a specified time has elapsed.
... setinterval() settimeout() works perfectly when you need to run code once after a set period of time.
...And 7 more matches

A first splash into JavaScript - Learn web development
you won't be expected to understand all of the code in detail immediately — we just want to introduce you to the high-level concepts for now, and give you an idea of how javascript (and other programming languages) work.
...the code syntax looks different, but the concepts are still largely the same.
...the game will end once the player guesses correctly, or once they run out of turns.
...And 7 more matches

Aprender y obtener ayuda - Learn web development
you concentrate deeply on a low-level topic and solving the specific problems that it brings.
... from the studies that neuroscientists have done on brain activity, we have found out that you can't really engage in both ways of learning — or thinking — at once.
... focused thinking is great for concentrating hard on specific subjects, getting into deep problem solving, and improving your mastery of the techniques required — strengthening the neural pathways in your brain where that information is stored.
...And 7 more matches

Signaling and video calling - Web APIs
once the two peers agree upon a mutually-compatible candidate, that candidate's sdp is used by each peer to construct and open a connection, through which media then begins to flow.
...we specify the autoplay attribute, ensuring once the video starts arriving, it immediately plays.
... once the rtcpeerconnection has been created, we request access to the user's camera and microphone by calling mediadevices.getusermedia(), which is exposed to us through the navigator.mediadevices.getusermedia property.
...And 7 more matches

Web Audio API - Web APIs
web audio concepts and usage the web audio api involves handling audio operations inside an audio context, and has been designed to allow modular routing.
...once the sound has been sufficiently processed for the intended effect, it can be linked to the input of a destination (audiocontext.destination), which sends the sound to the speakers or headphones.
... you can read about the theory of the web audio api in a lot more detail in our article basic concepts behind web audio api.
...And 7 more matches

Back to the Server: Server-Side JavaScript On The Rise - Archive of obsolete content
jaxer – server-side ajax via the firefox browser engine on the server although server-side javascript is not a new concept, jaxer implements it in a unique fashion.
...where once you would need to master not only javascript for the client-side but also some flavor of a server-side web language, jaxer puts all the rich capability of a server-side language into javascript.
... while most of the runat attribute values above are self explanatory, the server-proxy concept is best explained through example.
...And 6 more matches

Graceful asynchronous programming with Promises - Learn web development
so instead of waiting for the user, getting the chosen devices enabled, and directly returning the mediastream for the stream created from the selected sources, getusermedia() returns a promise which is resolved with the mediastream once it's available.
...it then calls getusermedia(), asking for a stream that has both video and audio tracks, then once that's been obtained, sets up a video element to show the stream coming from the camera as a "self view," then takes each of the stream's tracks and adds them to the webrtc rtcpeerconnection representing a connection to another user.
...the above functionality might look something like this: choosetoppings(function(toppings) { placeorder(toppings, function(order) { collectorder(order, function(pizza) { eatpizza(pizza); }, failurecallback); }, failurecallback); }, failurecallback); this is messy and hard to read (often referred to as "callback hell"), requires the failurecallback() to be called multiple times (once for each nested function), with other issues besides.
...And 6 more matches

Introduction to cross browser testing - Learn web development
objective: to gain an understanding of the high-level concepts involved in cross browser testing.
... once you've got an idea of the required featureset, and what technologies you will likely build these features with, you should start exploring the target audience — what browsers, devices, etc.
... once you've agreed on these details, you can go ahead and start developing the site.
...And 6 more matches

Introducing a complete toolchain - Learn web development
introducing our case study the toolchain that we are creating in this article will be used to build and deploy a mini site that lists data (taken from one of nasa's open apis) concerning potentially hazardous space objects that threaten our existence on earth!
... once you've signed up for github (click the sign up link on the homepage if you don't already have an account, and follow the instructions), you can use your github account for authentication on netlify (click sign up, then choose github from the "sign up with one of the following" list), so technically you only need to create one new account.
...there might be important decorations or music that help with your mental state — these are all important to doing your best work possible, and they should also only need to be set up once, if done properly.
...And 6 more matches

An overview of NSS Internals
once you have imported certificates and keys into the nss database, you can easily look them up and use them again.
...nss will usually create an in-memory (ram) presentation of certificates, once a certificate has been received from the network, read from disk, or looked up from the database, and prepare in-memory data structures that contain the certificate's properties, as well as providing a handle for the programmer to use.
... once the application is done with a handle, it should be released, allowing nss to free the associated resources.
...And 6 more matches

Bytecode Descriptions
both instructions would convert index to a property key for us, but the spec says to convert it only once.
...the spec requires that an objectliteral or arrayliteral creates a new object every time it's evaluated, so this instruction must not be used anywhere it might be executed more than once.
...used in derived class constructors to prohibit calling super more than once.
...And 6 more matches

JSAPI User Guide
once the functions are defined in global, any script that uses global as the global object can call them, just as any web page can call alert.
... in the environment we have created, the "hello world" script looks like this: system("echo hello world"); jsapi concepts this section aims to fill in the major gaps in the picture of the jsapi presented so far.
... once the c++ function returns false, the javascript engine starts unwinding the javascript stack, looking for a catch or finally block to execute.
...And 6 more matches

Starting WebLock
once you do this, the observer service implementing nsiobserverservice can notify your object of registered events by means of this interface, as in the figure below.
...once you have it, you can add the component to the category of components that get started automatically.
... once you have a nsiservicemanager reference, you can ask it for the service you are interested in.
...And 6 more matches

Viewpoints and viewers: Simulating cameras in WebXR - Web APIs
there are a few articles about the fundamental math, geometry, and other concepts behind webgl and webxr which may be useful to read before or while reading this one, including: explaining basic 3d theory matrix math for the web webgl model view projection geometry and reference spaces in webxr ed.
... once you've determined the matrix representing the combination of movements you wish the camera to make, you need to reverse it, because you're not moving the camera.
... composing multiple transforms if your camera needs to be performing multiple transforms simultaneously, such as zooming and panning at the same time, you can multiply the transform matrices together to compose them into a single matrix that applies both changes at once.
...And 6 more matches

Web Accessibility: Understanding Colors and Luminance - Accessibility
color, contrast, and luminance are among the most central and critical concepts to creating accessible web content with color.
...in others, "chroma" and "saturation" are two different concepts.
... for digital concerns, much of the technology has historically resided in the rgb color space.
...And 6 more matches

Introduction to XUL - Archive of obsolete content
this paper contains a short introduction to mozilla front-end architecture, concentrating on the task of building uis.
... applications, for instance, will have preconceived notions of what to do when they receive an "open file" command.
... we are at first primarily concerned with the obvious ui components: toolbars, menus and dialogs.
...And 5 more matches

Introduction to Public-Key Cryptography - Archive of obsolete content
this document introduces the basic concepts of public-key cryptography.
... the sections that follow introduce the concepts of public-key cryptography that underlie these capabilities.
...after entering this password once, the user doesn't need to enter it again for the rest of the session, even when accessing other ssl-enabled servers.
...And 5 more matches

Anatomy of a video game - Game development
this once-per-frame model is implemented in something called a main loop.
... modern javascript — as described in the next sections — thankfully makes it easy to develop an efficient, execute-once-per-frame main loop.
...because main() is called once in the second statement and every call of it places itself in the queue of things to do next frame, main() is synchronized to your framerate.
...And 5 more matches

Index - MDN Web Docs Glossary: Definitions of Web-related terms
the concept of a constructor can be applied to most object-oriented programming languages.
...it is the space between four intersecting grid lines and conceptually much like a table cell.
...for more information, read fetch basic concepts: guard.
...And 5 more matches

Cascade and inheritance - Learn web development
overview: building blocks next the aim of this lesson is to develop your understanding of some of the most fundamental concepts of css — the cascade, specificity, and inheritance — which control how css is applied to html and how conflicts are resolved.
...we encourage you to work through this section carefully, and check that you understand the concepts before moving on.
...the cascade, and the closely-related concept of specificity, are mechanisms that control which rule applies when there is such a conflict.
...And 5 more matches

Client-side storage - Learn web development
the user would only have to download the music files once — on subsequent visits they would be retrieved from the database instead.
... old school: cookies the concept of client-side storage has been around for a long time.
...once the request has succeeded, we clear the form inputs ready for entering the next note.
...And 5 more matches

Introduction to automated testing - Learn web development
once the install completes, test that node is installed by typing the following into the terminal, which returns the installed versions of node and npm: node -v npm -v if you've got node/npm already installed, you should update them to their latest versions.
... once all the questions have been asked, it will ask you if the information entered is ok.
... var build = gulp.parallel(html,css,js); exports.html = html; exports.css = css; exports.js = js; exports.build = build; /* * define default task that can be called by just running `gulp` from cli */ exports.default = build; further ideas once this is all set up, you can run the gulp command inside your project directory, and you should get an output like this: you can then try out the files output by your automated tasks by looking at them inside the build directory, and loading build/index.html in your web browser.
...And 5 more matches

Eclipse CDT
once your build is complete, mach can then generate a useful eclipse project on your behalf.
...rerun it (and then rebuild the index) once a week or so, or as necessary when you start to notice unusual code assistance issues that aren't fixed by rebuilding the index alone.
... headers are only parsed once for performance reasons, eclipse only processes header files that have include guards once, using the compiler options for the first source file it encounters that includes that header (eclipse bug 380511).
...And 5 more matches

AesCtrParams - Web APIs
a given counter block value must never be used more than once with the same key: given a message n blocks long, a different counter block must be used for every block.
... typically this is achieved by splitting the initial counter block value into two concatenated parts: a nonce (that is, a number that may only be used once).
... the nonce part of the block stays the same for every block in the message.
...And 5 more matches

Using readable streams - Web APIs
note: this article assumes that you understand the use cases of readable streams, and are aware of the high-level concepts.
... if not, we suggest that you first read the streams concepts and usage overview and dedicated streams api concepts article, then come back.
... creating your own custom readable stream the simple stream pump example we’ve been studying throughout this article includes a second part — once we’ve read the image from the fetch body in chunks, we then enqueue them into another, custom stream of our own creation.
...And 5 more matches

Establishing a connection: The WebRTC perfect negotiation pattern - Web APIs
perfect negotiation concepts perfect negotiation makes it possible to seamlessly and completely separate the negotiation process from the rest of your application's logic.
...as far as your application is concerned, it makes no difference whether you're calling out or receiving a call.
...however you make the determination, once these roles are assigned to the two peers, they can then work together to manage signaling in a way that doesn't deadlock and doesn't require a lot of extra code to manage.
...And 5 more matches

WebXR Device API - Web APIs
once both eyes' perspectives on the scene have been rendered, the resulting framebuffer is delivered to the webxr device to be presented to the user through their headset or other appropriate display device.
... webxr device api concepts and usage example webxr hardware setup while the older webvr api was designed solely to support virtual reality (vr), webxr provides support for both vr and augmented reality (ar) on the web.
...to get an xrframe, call the session's requestanimationframe() method, providing a callback which will be called with the xrframe once available.
...And 5 more matches

Populating the page: how browsers work - Web Performance
dns lookups usually only need to be done once per hostname for a page load.
... tcp handshake once the ip address is known, the browser sets up a connection to the server via a tcp three-way handshake.
... response once we have an established connection to a web server, the browser sends an initial http get request on behalf of the user, which for websites is most often an html file.
...And 5 more matches

ui/sidebar - Archive of obsolete content
once you've done that, you can show the sidebar by calling the sidebar's show() method.
... once you've finished using the sidebar you can destroy it by calling its dispose() method.
...once a sidebar has been created it can be shown and hidden in the active window using its show() and hide() methods.
...And 4 more matches

Creating Event Targets - Archive of obsolete content
create a new file in "lib" called "bookmarks.js", and add the following code: var { emit, on, once, off } = require("sdk/event/core"); var {cc, ci} = require("chrome"); var { xpcomutils }= require("resource://gre/modules/xpcomutils.jsm"); var bookmarkservice = cc["@mozilla.org/browser/nav-bookmarks-service;1"] .getservice(ci.nsinavbookmarksservice); var bookmarkobserver = { onitemadded: function(aitemid, afolder, aindex) { emit(exports, "added", bookmarkservic...
...e.getbookmarkuri(aitemid).spec); }, onitemvisited: function(aitemid, avisitid, time) { emit(exports, "visited", bookmarkservice.getbookmarkuri(aitemid).spec); }, queryinterface: xpcomutils.generateqi([ci.nsinavbookmarkobserver]) }; bookmarkservice.addobserver(bookmarkobserver, false); exports.on = on.bind(null, exports); exports.once = once.bind(null, exports); exports.removelistener = function removelistener(type, listener) { off(exports, type, listener); }; this code implements a module which can emit added and visited events.
... it duplicates the previous code, but with a few changes: import emit(), on(), once(), and off() from event/core replace listener functions with calls to emit(), passing the appropriate event type export its own event api.
...And 4 more matches

Using XPInstall to Install Plugins - Archive of obsolete content
xpi packages make use of different apis from within install.js, although the concept is the same.
...once again, this step involves calls to getfolder to locate a "well known" directory in which to install to as a secondary install location.
... on windows, the windows registry keys mentioned above follow a nomenclature using the concept of a plugin identifier as the name of the key under the mozillaplugins subkey.
...And 4 more matches

Applying color to HTML elements using CSS - HTML: Hypertext Markup Language
how to describe a color in order to represent a color in css, you have to find a way to translate the analog concept of "color" into a digital form that a computer can use.
...the concept is the same anywhere you use color.
... the advantage to averaging colors can be that often what looks like a solid color is actually a surprisingly varied number of related colors all used in concert, blending to create a desired effect.
...And 4 more matches

Iterators and generators - JavaScript
iterators and generators bring the concept of iteration directly into the core language and provide a mechanism for customizing the behavior of for...of loops.
... once created, an iterator object can be iterated explicitly by repeatedly calling next().
... iterating over an iterator is said to consume the iterator, because it is generally only possible to do once.
...And 4 more matches

lang/functional - Archive of obsolete content
arguments : mixed additional arguments to pass to fn upon execution once(fn) creates a version of the input function that can only be called one time.
... let { once } = require("sdk/lang/functional"); let setup = once(function (env) { // initializing important things console.log("successfully initialized " + env); return 1; // assume success and return 1 }); setup('dev'); // returns 1 // prints "successfully initialized dev" // future attempts to call this function just return the cached // value that was returned previously setup('production'); // returns 1 // no print message is displayed since the function isn't executed parameters fn : function the function that will be executed only once inside the once wrapper.
... returns function : the wrapped fn that can only be executed once.
...And 3 more matches

Appendix D: Loading Scripts - Archive of obsolete content
although wary authors can choose to cache instances of their modules so that modules are loaded only once globally, this method can be easily misused to re-load scripts for each new window where they would be better loaded only once globally per session.
...in addition to the possible performance concerns, passing data between these compartments is not entirely transparent.
...although wary authors can choose to cache instances of their modules so that modules are loaded only once globally, this method can be easily misused to re-load scripts for each new window where they would be better loaded only once globally per session.
...And 3 more matches

The web and web standards - Learn web development
in 1980, tim berners-lee (often referred to as timbl) wrote a notebook program called enquire, which featured the concept of links between different nodes.
...once you embrace the constant change and uncertainty of the web, you'll start to enjoy yourself.
...the following simple javascript will store a reference to our paragraph in memory and change the text inside it: let pelem = document.queryselector('p'); pelem.textcontent = 'we changed the text!'; in the house analogy, javascript is like the cooker, tv, microwave, or hairdryer — the things that give your house useful functionality tooling once you've learned the "raw" technologies that can be used to build web pages (such as html, css, and javascript), you'll soon start to come across various tools that can be used to make your work easier or more efficient.
...And 3 more matches

Introduction to events - Learn web development
in this article, we discuss some important concepts surrounding events, and look at how they work in browsers.
...the node.js event model relies on listeners to listen for events and emitters to emit events periodically — it doesn't sound that different, but the code is quite different, making use of functions like on() to register an event listener, and once() to register an event listener that unregisters after it has run once.
... other event concepts in this section, we briefly cover some advanced concepts that are relevant to events.
...And 3 more matches

Functions — reusable blocks of code - Learn web development
previous overview: building blocks next another essential concept in coding is functions, which allow you to store a piece of code that does a single task inside a defined block, and then call that code whenever you need it using a single short command — rather than having to type out the same code multiple times.
... in this article we'll explore fundamental concepts behind functions such as basic syntax, how to invoke and define them, scope, and parameters.
... objective: to understand the fundamental concepts behind javascript functions.
...And 3 more matches

Mozilla accessibility architecture
readers of this document should be familiar with interfaces, the w3c dom, xul and the concept of a layout object tree.
...in general, the accessibility apis use similar concepts, but use different method, constant and interfaces names.
...it can read in an entire document at once, look only pieces of a document related to recent events, or traverse the accessibility object model based on screen position.
...And 3 more matches

OS.File for the main thread
promise = promise.then(function onsuccess() { // once loop is complete, finalize.
... note that the operating system limits the number of files that can be opened simultaneously by one process, so do not forget to close that file once you have finished it, to ensure that you are not blocking the rest of the process.
...if specified, write the data to a temporary file called tmppath and, once the write is complete, rename the file to replace path.
...And 3 more matches

DMD
look at the "trigger" section below to see the full list of ways to get a dmd report once you have it activated.
... adb shell su # you need root access for the setprop command to take effect setprop wrap.org.mozilla.fennec_$username "/data/local/tmp/dmd_fennec" once this is set up, starting the org.mozilla.fennec_$username app will use the wrapper script.
... "once-reported stack trace records": like the "unreported stack trace records" section, but for blocks reported once.
...And 3 more matches

Index
this hook does not implement iteration: once the properties are defined, the javascript engine can enumerate them.
... 154 jsstring jsapi reference, needscontent, spidermonkey conceptually, a javascript string is just an array of char16_t characters and a length.
...it calls the dump function once for each named root in the given runtime rt.
...And 3 more matches

An Overview of XPCOM
the book is presented as a tutorial about creating xpcom components, but it covers all major aspects, concepts, and terminology of the xpcom component model along the way.
... this chapter provides a quick tour of xpcom - an introduction to the basic concepts and technologies in xpcom and component development.
... the brief sections in this chapter introduce the concepts at a very high level, so that we can discuss and use them with more familiarity in the tutorial itself, which describes the creation of a mozilla component called weblock.
...And 3 more matches

Storage
binding multiple sets of parameters starting in gecko 1.9.2 (firefox 3.6), there's a new, more convenient way to bind multiple sets of parameters at once prior to executing your statement asynchronously.
...once all the parameters are set up, a single call to mozistoragestatement.bindparameters() will ensure that the parameters are bound before execution.
... mozstoragestatementscoper scoper(mspecialstatement); // you can use mspecialstatement without concern now.
...And 3 more matches

LocalFileSystem - Web APIs
basic concepts this section includes a few key concepts for the methods.
... you can call the method more than once if you want to create two file systems: one that's temporary and one that's persistent.
... (to learn more about the storage types, see the basic concepts article.) in most cases, you need to create only one file system, but in a few cases, it might be useful to create a second one.
...And 3 more matches

Adding 2D content to a WebGL context - Web APIs
« previousnext » once you've successfully created a webgl context, you can start rendering into it.
... fragment shader the fragment shader is called once for every pixel on each shape to be drawn, after the shape's vertices have been processed by the vertex shader.
... once the shader has the source code, it's compiled using gl.compileshader().
...And 3 more matches

Using Web Workers - Web APIs
once created, a worker can send messages to the javascript code that created it by posting messages to an event handler specified by that code (and vice versa).
... this example is rather trivial, but we decided to keep it simple while introducing you to basic worker concepts.
... here we'll concentrate on the differences between dedicated and shared workers.
...And 3 more matches

HTTP conditional requests - HTTP
http has a concept of conditional requests, where the result, and even the success of a request, can be changed by comparing the affected resources with the value of a validator.
...these validators are cached with the resource (like all headers) and will be used to craft conditional requests, once the cache becomes stale.
...but once it has become stale, this is mostly controlled by the cache-control header, the client doesn't use the cached value directly but issues a conditional request.
...And 3 more matches

CSP: style-src - HTTP
'nonce-<base64-value>' an allow-list for specific inline scripts using a cryptographic nonce (number used once).
... the server must generate a unique nonce value each time it transmits a policy.
... it is critical to provide an unguessable nonce, as bypassing a resource’s policy is otherwise trivial.
...And 3 more matches

A re-introduction to JavaScript (JS tutorial) - JavaScript
the fourth edition was abandoned, due to political differences concerning language complexity.
... unlike most programming languages, the javascript language has no concept of input or output.
...the first is good for basic looping; the second for loops where you wish to ensure that the body of the loop is executed at least once: while (true) { // an infinite loop!
...And 3 more matches

panel - Archive of obsolete content
this may take one of the following values: "start": load content scripts immediately after the document element for the panel is inserted into the dom, but before the dom content itself has been loaded "ready": load content scripts once dom content has been loaded, corresponding to the domcontentloaded event "end": load content scripts once all the content (dom, js, css, images) for the panel has been loaded, at the time the window.onload event fires this property is optional and defaults to "end".
... once a panel object has been created it can be shown and hidden using its show() and hide() methods.
... once a panel is no longer needed it can be deactivated using destroy().
...And 2 more matches

event/target - Archive of obsolete content
users of the object can listen to the events using the standard on() and once() functions.
...eventtarget interface defines convenience method for adding one shot event listeners via method once.
... such listeners are called only once next time event of the specified type is emitted: target.once('ready', function onready() { // do the thing once ready!
...And 2 more matches

MCD, Mission Control Desktop, AKA AutoConfig - Archive of obsolete content
e); //smtp general lockpref("mail.smtp.defaultserver", "smtp1"); lockpref("mail.smtpserver.smtp1.auth_method", 0); lockpref("mail.smtpserver.smtp1.hostname", "smtp-int.int-evry.fr"); lockpref("mail.smtpserver.smtp1.port", 25); lockpref("mail.smtpserver.smtp1.try_ssl", 0); lockpref("mail.smtpserver.smtp1.username", ""); lockpref("mail.smtpservers", "smtp1"); lockpref("mail.startup.enabledmailcheckonce", true); lockpref("mailnews.quotingprefs.version", 1); lockpref("mailnews.ui.threadpane.version", 5); /* 3) define here (because if set after "4)" below it doesn't work!) processldapvalues which is eventually called by getldapattributes() just below, check getldapattributes() code from $mozilla_home/defaults/autoconfig/prefcalls.js to see the inside call to "user defined" processldapvalues */ f...
...p lockpref("mail.identity.id1.smtpserver", "smtp1"); defaultpref("mail.smtpserver.smtp1.auth_method", 0); lockpref("mail.smtpservers", "smtp1"); lockpref("mail.smtpservers", "smtp1"); lockpref("mail.smtp.defaultserver", "smtp1"); lockpref("mail.smtpserver.smtp1.hostname", "smtp-int.int-evry.fr"); lockpref("mail.identity.id1.organization", "int evry france"); lockpref("mail.startup.enabledmailcheckonce", true); lockpref("mail.ui.folderpane.version", 3); lockpref("mailnews.ui.threadpane.version", 2); //ldap config lockpref("mail.identity.id1.directoryserver", "ldap_2.servers.ldapint"); lockpref("ldap_2.prefs_migrated", true); lockpref("ldap_2.servers.history.filename", "history.mab"); lockpref("ldap_2.servers.history.replication.lastchangenumber", 0); lockpref("ldap_2.servers.ldapint.auth.savep...
...mail.identity.id1.smtpserver", "smtp1"); defaultpref("mail.smtpserver.smtp1.auth_method", 0); defaultpref("mail.smtpservers", "smtp1"); defaultpref("mail.smtpservers", "smtp1"); defaultpref("mail.smtp.defaultserver", "smtp1"); defaultpref("mail.smtpserver.smtp1.hostname", "smtp-int.int-evry.fr"); lockpref("mail.identity.id1.organization", "int evry france"); lockpref("mail.startup.enabledmailcheckonce", true); lockpref("mail.ui.folderpane.version", 3); lockpref("mailnews.ui.threadpane.version", 2); //ldap config lockpref("mail.identity.id1.directoryserver", "ldap_2.servers.ldapint"); lockpref("ldap_2.prefs_migrated", true); lockpref("ldap_2.servers.history.filename", "history.mab"); lockpref("ldap_2.servers.history.replication.lastchangenumber", 0); lockpref("ldap_2.servers.ldapint.auth.savep...
...And 2 more matches

Mozilla Crypto FAQ - Archive of obsolete content
you should contact those vendors or developers directly for more information concerning their plans.
...you do not need to provide such notification in any case, but you may need to take other actions to comply with laws and regulations in your own country concerning encryption technologies.
... however, in an advisory opinion issued in reference to the bernstein case, the bureau of export administration (bxa) has stated the following: "concerning the posting onto a mirror or archive site of already-posted source code, notification is required only for the initial posting." bxa and nsa have already been notified of the posting of encryption-related source code on the mozilla site, and in light of this opinion we have therefore decidednot to ask mirror sites to provide notification themselves.
...And 2 more matches

A XUL Bestiary - Archive of obsolete content
this xulnote presents some of the key concepts and terms in the xul development environment.
...i selected items for this group because they seemed to be either shrouded in mystery, misused as concepts or terms, or underestimated according to their role in xul and cross-platform development.
... the chrome url this concept of a chrome as an integrated, dynamic thing in some way divorced from the "appcore" is realized in the use of the chrome url to point to chunks of xul and their related files.
...And 2 more matches

Index - Archive of obsolete content
3 a xul bestiary add-ons, extensions, needstechnicalreview, xul this xulnote presents some of the key concepts and terms in the xul development environment.
...i selected items for this group because they seemed to be either shrouded in mystery, misused as concepts or terms, or underestimated according to their role in xul and cross-platform development.
...it explains the concept of dom documents, demonstrates a few simple examples of using dom calls to perform basic manipulations on a document, and then demonstrates working with anonymous xbl content using mozilla-specific methods.
...And 2 more matches

More Event Handlers - Archive of obsolete content
example 1 : source view <vbox oncommand="alert(event.currenttarget.tagname);"> <button label="ok"/> <checkbox label="show images"/> </vbox> stop event propagation once you handle an event, regardless of where in the propagation the event is, you will likely want to stop the event from being sent to further elements, essentially stopping the capturing or bubbling phases from continuing.
...note that once propagation or the default action has been prevented, neither may be re-enabled again for that event.
...the click event will be fired once for the first click, again for the second click, and again for the third click, but the dblclick event will only be fired once for a double click.
...And 2 more matches

WebVR — Virtual Reality for the Web - Game development
the concept of virtual reality in itself isn't new, but now we have the technology to have it working as it should be, and a javascript api to make use of it in web applications.
... note: for more information, read our webvr concepts article.
... using the webvr api the webvr api is based on two concepts — sending stereoscopic images to both lenses in your headset and receiving positional data for your head from the sensor, and those two are handled by hmdvrdevice (head-mounted display virtual reality device) and positionsensorvrdevice.
...And 2 more matches

Mobile accessibility - Learn web development
once you've selected the option you want, double-click to choose that option.
... once you've finished, find the enter key and press it.
... once voiceover is enabled, ios's basic control gestures will be a bit different: a single tap will cause the item you tap on to be selected; your device will speak the item you've tapped on.
...And 2 more matches

The box model - Learn web development
in the rest of the lesson, we will concentrate on the outer display type.
...the properties used in that example are shorthands and allow us to set all four sides of the box at once.
... we can control all margins of an element at once using the margin property, or each side individually using the equivalent longhand properties: margin-top margin-right margin-bottom margin-left in the example below, try changing the margin values to see how the box is pushed around due to the margin creating or removing space (if it is a negative margin) between this element and the containing element.
...And 2 more matches

Making asynchronous programming easier with async and await - Learn web development
once that's complete, your code continues to execute starting on the next line.
...once the response is available, the parser moves to the next line, which creates a blob out of it.
...let's have a look at some examples that prove the concept.
...And 2 more matches

JavaScript building blocks - Learn web development
looping code sometimes you need a task done more than once in a row.
... functions — reusable blocks of code another essential concept in coding is functions.
...in this article we'll explore fundamental concepts behind functions such as basic syntax, how to invoke and define functions, scope, and parameters.
...And 2 more matches

Deployment and next steps - Learn web development
ction dev: !production, // we'll extract any component css out into // a separate file - better for performance css: css => { css.write('public/build/bundle.css'); } }), later on in the same file you'll also see how rollup minimizes our scripts in production mode and launches a local server in development mode: // in dev mode, call `npm run start` once // the bundle has been generated !production && serve(), // watch the `public` directory and refresh the // browser on changes when not in production !production && livereload('public'), // if we're building for production (npm run build // instead of npm run dev), minify production && terser() ], there are many plugins for rollup that allow you to customize i...
... once it has finished deploying, go to the "production" url in your browser, and you'll see the app deployed!
... once gitlab finishes building and publishing your app, it will be accessible at https://your-user.gitlab.io/mdn-svelte-todo/; in my case it's https://opensas.gitlab.io/mdn-svelte-todo/.
...And 2 more matches

Eclipse CDT Manual Setup
once you've added this folder, delete the existing output folder that was set to the root of the project.
...(see the headers are only parsed once section below to understand why this step is important for people who have their object directory outside their source tree.) getting code assistance working you're now ready to get code assistance working.
... building the index once you see the end of the build output in the console tab and the build item has disappeared from the progress tab, you can start indexing the source.
...And 2 more matches

Localization sign-off reviews
once attached, open the attachment details.
... once you have made the formal request in bugzilla and you have pushed your work into your l10n repo, refer to the dashboards to follow your review's progress.
...once filed, they appear on your dashboard for you to fix.
...And 2 more matches

Mozilla DOM Hacking Guide
static nsresult init(): called only once, it is used to initialize the remaining members of the nsdomclassinfodata structure, as mentioned above.
... once called, init() sets sisinitialized to true, to remember that the initialization has been performed.
... nsdomclassinfo::init() this method is to be called only once.
...And 2 more matches

Mozilla Development Strategies
make sure documentation gets updated if the bug you're fixing is likely to require an update to developer documentation once it's fixed, be sure to add the dev-doc-needed keyword to the bug (or ask someone to do it, if you don't have editbugs privileges on bugzilla).
... this puts the bug on the radar of our documentation team to ensure that once the bug is resolved, the documentation will be updated appropriately.
...it's easier to do it right once, when your mind is in the problem, than to do it once quickly and then have to come back and do it again the right way.
...And 2 more matches

sslintro.html
an ssl application typically includes five parts: initialization configuration communication functions used by callbacks cleanup although the details differ somewhat for client and server applications, the concepts and many of the functions are the same for both.
...nss_init is not idempotent, so call it only once.
...this function must be called once for each default value that needs to be changed.
...And 2 more matches

Redis Tips
a transaction block is a series of commands sent all at once across the wire.
... optimistic locking your transactions are atomic once they start, but of course you can't guarantee that you'll get there first.
... that means you can subscribe to a bunch of channels at once.
...And 2 more matches

Handling Mozilla Security Bugs
in particular, we understand and acknowledge the concerns of those who believe that all information about security vulnerabilities should be publicly disclosed as soon as it is known, so that users may take immediate steps to protect themselves and so that problems can get the maximum amount of developer attention and be fixed as soon as possible.
...we understand and acknowledge the concerns of those who believe that too-hasty disclosure of exploit details can provide a short-term advantage to potential attackers, who can exploit a problem before most end users become aware of its existence.
... we believe that both sets of concerns are valid, and that both are worth addressing as best we can.
...And 2 more matches

Avoiding leaks in JavaScript XPCOM components
take every information on this site with a grain of salt, although most concepts and best practices still apply.
...this document attempts to help them do so, first by explaining the underlying concepts, and second by describing a number of common javascript patterns that cause leaks.
...we currently implement this by making the wrapper a root in the javascript garbage collector once somebody sets a javascript property on a dom node.
...And 2 more matches

Creating the Component Code
once enabled, this "weblock" mode is password protected and persists until it is turned off by the password holder.
...web lock user interface shows the icon that is used to activate the web lock mode (leftmost in the status bar) once you have installed the weblock component and the extra user interface.
... once your component implements these interfaces, the rest of the registration process itself is simple.
...And 2 more matches

Introduction to XPCOM for the DOM
pushing this concept to its maximum, a class can be "purely virtual" if it declares methods without implementing any of them.
...xpcom pushes this concept to the extreme.
...if you are concerned that it could return ns_nointerface, return ns_ok, as the previous example shows.
...And 2 more matches

Address Book examples
once you have an object that implements nsiabcollection (see above), you can search for cards with particular properties within that collection using getcardfromproperty.
... editing contacts once you have obtained a card from an nsiabdirectory (see above), you can edit it in a two step process, firstly, change the properties that you to edit: card.setproperty("firstname", "jane"); card.setproperty("lastname", "doe"); secondly, call modifycard to save the card in the database.
... addressbook.modifycard(card); deleting contacts once you have obtained a card(s) from an nsiabdirectory (see above) you can delete one or more simply by calling the deletecards function: let cardstodelete = components.classes["@mozilla.org/array;1"] .createinstance(components.interfaces.nsimutablearray); cardstodelete.appendelement(card); // repeat append as necessary addressbook.deletecards(cardstodelete); how do i add and use my own properties?
...And 2 more matches

Debugger - Firefox Developer Tools
(note that each rule is only applied once in the process of resolving a givenglobal argument.
...each source appears only once in the array.query is an object whose properties restrict which sources are returned; a source must meet all the criteria given byquery to be returned.
...each instance appears only once in the array.query is an object whose properties restrict which scripts are returned; a script must meet all the criteria given byquery to be returned.
...And 2 more matches

Intersection Observer API - Web APIs
one thing the intersection observer api can't tell you: the exact number of pixels that overlap or specifically which ones they are; however, it covers the much more common use case of "if they intersect by somewhere around n%, i need to do something." intersection observer concepts and usage the intersection observer api allows you to configure a callback that is called: (1) whenever one element, called the target, intersects either the device viewport or a specified element; for the purpose of this api, this is called the root element or root (2) and whenever the observer is asked to watch a target for the very first time typically, you'll want to watch for intersec...
... targeting an element to be observed once you have created the observer, you need to give it a target element to watch: let target = document.queryselector('#listitem'); observer.observe(target); // the callback we setup for the observer will be executed now for the first time // it waits until we assign a target to our observer (even if the target is currently not visible) whenever the target meets a threshold specified for the inte...
... we call window.addeventlistener() to start listening for the load event; once the page has finished loading, we get a reference to the element with the id "box" using queryselector(), then call the createobserver() method we'll create in a moment to handle building and installing the intersection observer.
...And 2 more matches

MediaDevices.getUserMedia() - Web APIs
privacy and security as an api that may involve significant privacy concerns, getusermedia()'s specification lays out a wide array of privacy and security requirements that browsers are obligated to meet.
... user privacy as an api that may involve significant privacy concerns, getusermedia() is held by the specification to very specific requirements for user notification and permission management.
...browsers may offer a once-per-domain permission feature, but they must ask at least the first time, and the user must specifically grant ongoing permission if they choose to do so.
...And 2 more matches

WebGLRenderingContext.bufferData() - Web APIs
possible values: gl.static_draw: the contents are intended to be specified once by the application, and used many times as the source for webgl drawing and image specification commands.
... gl.stream_draw: the contents are intended to be specified once by the application, and used at most a few times as the source for webgl drawing and image specification commands.
... when using a webgl 2 context, the following values are available additionally: gl.static_read: the contents are intended to be specified once by reading data from webgl, and queried many times by the application.
...And 2 more matches

A simple RTCDataChannel sample - Web APIs
starting up when the script is run, we set up an load event listener, so that once the page is fully loaded, our startup() function is called.
... once the answer has been created, it's passed into the remoteconnection by calling rtcpeerconnection.setlocaldescription().
... note: once again, this process is not a real-world implementation; in normal usage, there's two chunks of code running on two machines, interacting and negotiating the connection.
...And 2 more matches

Using DTMF with WebRTC - Web APIs
once the track is selected, you can obtain from its rtcrtpsender the rtcdtmfsender object you'll use for sending dtmf.
...once the tones finish transmitting, the connection is closed.
... once both the caller's and the receiver's media tracks are all stopped, we pause the <audio> element and set its srcobject to null.
...And 2 more matches

Using WebRTC data channels - Web APIs
once you've established a webrtc peer connection using the rtcpeerconnection interface, you're able to send and receive media data between the two peers on the connection.
... messages smaller than 16kib can be sent without concern, as all major user agents handle them the same way.
... concerns with large messages currently, it's not practical to use rtcdatachannel for messages larger than 64kib (16kib if you want to support cross-browser exchange of data).
...And 2 more matches

Lighting a WebXR setting - Web APIs
because the webxr device api relies on other technologies—namely, webgl and frameworks based upon it—to perform all rendering, texturing, and lighting of a scene, the same general lighting concepts apply to webxr settings or scenes as to any other webgl-generated display.
... lighting issues for mixed reality content in addition to the usual issues that you need to contend with while lighting a scene, the vr or ar use case adds additional areas of concern when writing your shaders.
...you can learn all about the proposed api and a fair amount about the concept of lighting estimation in the explainer documnent that's included in the specification's github repository.
...And 2 more matches

Background audio processing using AudioWorklet - Web APIs
the input and output lists the lists of inputs and outputs can be a little confusing at first, even though they're actually very simple once you realize what's going on.
...however, once this chrome issue is fixed, you will want to change this behavior if possible as it may have a slight negative impact on performance.
...once that's done, it instantiates and returns a new audioworkletnode.
...And 2 more matches

WindowOrWorkerGlobalScope.setInterval() - Web APIs
arg1, ..., argn optional additional arguments which are passed through to the function specified by func once the timer expires.
... console.log(a); console.log(b); } example 2: alternating two colors the following example calls the flashtext() function once a second until the stop button is pressed.
...example: var intervalid = setinterval(function(arg1) {}.bind(undefined, 10), 1000); inactive tabs requires gecko 5.0(firefox 5.0 / thunderbird 5.0 / seamonkey 2.2) starting in gecko 5.0 (firefox 5.0 / thunderbird 5.0 / seamonkey 2.2), intervals are clamped to fire no more often than once per second in inactive tabs.
...And 2 more matches

ARIA Test Cases - Accessibility
- n/a n/a jaws 10 pass fail - - voiceover (leopard) n/a n/a - fail window-eyes - - - - nvda - n/a - - zoom (leopard) pass n/a pass pass zoomtext - - - - orca - - - - drag and drop tic tac toe slide show expected at behavior: (mz) once focusing or arrowing onto the draggable item, screen reader should indicate that item can be an object that can be dragged.
... once marked for drag and drop, screen reader should announce that this item has been picked up, to distinguish it from others that may be draggable, but are currently not selected for the operation.
...note that for tabs with ajax content, for performance reasons it is optional that they only load the panel only once the user presses space on the new tab.
...And 2 more matches

CSS Box Alignment - CSS: Cascading Style Sheets
this document details the general concepts found in the specification.
... key concepts and terminology the specification details some alignment terminology to make it easier to discuss these alignment properties outside of their implementation within a particular layout method.
... there are also some key concepts which are common to all layout methods.
...And 2 more matches

Controlling Ratios of Flex Items Along the Main Axis - CSS: Cascading Style Sheets
.item { flex: 2 1 auto; } if you have read the article basic concepts of flexbox, then you will have already had an introduction to the properties.
... important concepts when working on the main axis there are a few concepts worth digging into before looking at how the flex properties work to control ratios along the main axis.
... these relate to the natural size of flex items before any growing or shrinking takes place, and to the concept of free space.
...And 2 more matches

Mastering Wrapping of Flex Items - CSS: Cascading Style Sheets
flexbox was designed as a single dimensional layout, meaning that it deals with laying out items as a row or as a column — but not both at once.
...if you want to cause them to wrap once they become too wide you must add the flex-wrap property with a value of wrap, or use the shorthand flex-flow with values of row wrap or column wrap.
...once the first row gets to a point where there is not enough space to place another 160 pixel item, a new flex line is created for the items and so on until all of the items are placed.
...And 2 more matches

Relationship of flexbox to other layout methods - CSS: Cascading Style Sheets
there is a note in the flexbox spec stating that in the future, once it is completed, the definitions in box alignment level 3 will supersede those of flexbox: "note: while the alignment properties are defined in css box alignment [css-align-3], flexible box layout reproduces the definitions of the relevant ones here so as to not create a normative dependency that may slow down advancement of the spec.
...additionally, any new values defined in the box alignment module will apply to flexible box layout; in otherwords, the box alignment module, once completed, will supercede the definitions here." in a later article in this series — aligning items in a flex container — we will take a thorough look at how the box alignment properties apply to flex items.
... writing modes in the basic concepts of flexbox article, i explained that flexbox is writing mode aware.
...And 2 more matches

Box alignment in CSS Grid Layout - CSS: Cascading Style Sheets
a b b b b" "a a a a b b b b" "c c c c d d d d" "c c c c d d d d"; align-items: start; } .item1 { grid-area: a; } .item2 { grid-area: b; } .item3 { grid-area: c; } .item4 { grid-area: d; } <div class="wrapper"> <div class="item1">item 1</div> <div class="item2">item 2</div> <div class="item3">item 3</div> <div class="item4">item 4</div> </div> keep in mind that once you set align-items: start, the height of each child <div> will be determined by the contents of the <div>.
...this will mimic the correct behavior once implemented.
... once again the default is stretch, other than for items with an intrinsic aspect ratio.
...And 2 more matches

CSS grids, logical values, and writing modes - CSS: Cascading Style Sheets
block and inline once we begin dealing with logical, rather than physical properties, we stop seeing the world as left to right, and top to bottom.
...this occurs once we've flipped the grid onto the side, like this: * {box-sizing: border-box;} .wrapper { border: 2px solid #f76707; border-radius: 5px; background-color: #fff4e6; } .wrapper > div { border: 2px solid #ffa94d; border-radius: 5px; background-color: #ffd8a8; padding: 1em; color: #d9480f; } .wrapper { writing-mode: vertical-lr; display: grid; grid-template...
...once you realize that grid-area sees the world as "block and inline", you can remember that we are setting the two starts, then the two ends.
...And 2 more matches

CSS Grid Layout and Progressive Enhancement - CSS: Cascading Style Sheets
if they tend to use up-to-date versions of firefox, chrome, opera, and safari, then it would make sense to start using css grids once those browsers update.
... as a concession for older browsers, i have set a min-height on the items, and hope that my content editors won’t add too much content and make a mess of the layout!
... once again i can use feature queries to overwrite a layout that uses display: inline-block, and again i don’t need to overwrite everything.
...And 2 more matches

<color> - CSS: Cascading Style Sheets
threeddarkshadow the color of the darker (generally outer) of the two borders away from the light source for 3-d elements that appear 3-d due to two concentric layers of surrounding border.
... threedface the face background color for 3-d elements that appear 3-d due to two concentric layers of surrounding border.
... threedhighlight the color of the lighter (generally outer) of the two borders facing the light source for 3-d elements that appear 3-d due to two concentric layers of surrounding border.
...And 2 more matches

CSS: Cascading Style Sheets
css reference our exhaustive css reference for seasoned web developers describes every property and concept of css.
... styling text with the basics of the css language covered, the next css topic for you to concentrate on is styling text — one of the most common things you'll do with css.
...now it's time to look at how to place your boxes in the right place concerning the viewport, and one another.
...And 2 more matches

Connection management in HTTP/1.x - HTTP
these connections were short-lived: a new one created each time a request needed sending, and closed once the answer had been received.
... a related topic is the concept of http connection upgrades, wherein an http/1.1 connection is upgraded to a different protocol, such as tls/1.0, websocket, or even http/2 in cleartext.
...to ease these problems, the concept of a persistent connection has been designed, even prior to http/1.1.
...And 2 more matches

CSP: base-uri - HTTP
'nonce-<base64-value>' an allow-list for specific inline scripts using a cryptographic nonce (number used once).
... the server must generate a unique nonce value each time it transmits a policy.
... it is critical to provide an unguessable nonce, as bypassing a resource’s policy is otherwise trivial.
...And 2 more matches

CSP: default-src - HTTP
'nonce-<base64-value>' an allow-list for specific inline scripts using a cryptographic nonce (number used once).
... the server must generate a unique nonce value each time it transmits a policy.
... it is critical to provide an unguessable nonce, as bypassing a resource’s policy is otherwise trivial.
...And 2 more matches

CSP: form-action - HTTP
'nonce-<base64-value>' an allow-list for specific inline scripts using a cryptographic nonce (number used once).
... the server must generate a unique nonce value each time it transmits a policy.
... it is critical to provide an unguessable nonce, as bypassing a resource’s policy is otherwise trivial.
...And 2 more matches

CSP: img-src - HTTP
'nonce-<base64-value>' an allow-list for specific inline scripts using a cryptographic nonce (number used once).
... the server must generate a unique nonce value each time it transmits a policy.
... it is critical to provide an unguessable nonce, as bypassing a resource’s policy is otherwise trivial.
...And 2 more matches

CSP: navigate-to - HTTP
'nonce-<base64-value>' an allow-list for specific inline scripts using a cryptographic nonce (number used once).
... the server must generate a unique nonce value each time it transmits a policy.
... it is critical to provide an unguessable nonce, as bypassing a resource’s policy is otherwise trivial.
...And 2 more matches

CSP: script-src-attr - HTTP
'nonce-<base64-value>' an allow-list for specific inline scripts using a cryptographic nonce (number used once).
... the server must generate a unique nonce value each time it transmits a policy.
... it is critical to provide an unguessable nonce, as bypassing a resource’s policy is otherwise trivial.
...And 2 more matches

CSP: script-src-elem - HTTP
'nonce-<base64-value>' an allow-list for specific inline scripts using a cryptographic nonce (number used once).
... the server must generate a unique nonce value each time it transmits a policy.
... it is critical to provide an unguessable nonce, as bypassing a resource’s policy is otherwise trivial.
...And 2 more matches

Web video codec guide - Web media technologies
this guide introduces the video codecs you're most likely to encounter or consider using on the web, summaries of their capabilities and any compatibility and utility concerns, and advice to help you choose the right codec for your project's video.
...once an artifact has appeared, it may linger for a while, because of how video is displayed.
... [1] firefox support for avc is dependent upon the operating system's built-in or preinstalled codecs for avc and its container in order to avoid patent concerns.
...And 2 more matches

Performance fundamentals - Web Performance
this is a familiar concept: everyone prefers, say, games that display 60 frames per second over ones that display 10 frames per second, even if they can't explain why.
...intelligently allocating memory to user state is an important concern that we go over in more detail below.
...firefox is highly optimized to scroll arbitrary content; this is usually not a concern.
...And 2 more matches

Mobile first - Progressive web apps (PWAs)
this article offers some related ideas, looking at the concept of mobile first — the practice of designing a website so that the default layout/configuration is for mobile devices, and layouts and features for desktop browsers are then layered on top of that default.
... first things first — mobile as a default you may think that concentrating on the mobile experience first sounds pointless, as we are more used to dealing with desktop sites, and we surely need to consider the full gamut of features for the overall experience across desktop, mobile, etc., before then paring it down to a mobile experience that is simpler, more streamlined, or whatever.
...of course, your users will be concentrating on what they're doing, but they are likely to be in a car with bad lighting, or in a noisy bar with the sport on tv in the background!
...And 2 more matches

Communicating using "port" - Archive of obsolete content
once(): listen to only the first occurrence of a message.
... port.once() often you'll want to receive a message just once, then stop listening.
... the port object offers a shortcut to do this: the once() method.
... this example rewrites the "listener.js" content script in the port.removelistener() example so that it uses once(): function getfirstparagraph() { var paras = document.getelementsbytagname('p'); console.log(paras[0].textcontent); } self.port.once("get-first-para", getfirstparagraph); json-serializable values the payload for an message can be any json-serializable value.

page-mod - Archive of obsolete content
in this case the listener assigned to onattach is called once for each loaded document, and the add-on code will have a separate worker for each document.
... the option takes a single string that may take any one of the following values: "start": load content scripts immediately after the document element is inserted into the dom, but before the dom content itself has been loaded "ready": load content scripts once dom content has been loaded, corresponding to the domcontentloaded event "end": load content scripts once all the content (dom, js, css, images) has been loaded, at the time the window.onload event fires var pagemod = require("sdk/page-mod"); pagemod.pagemod({ include: "*", contentscript: 'window.alert("matched!");', contentscriptwhen: "start" }); if you specify "start...
...once created a page-mod will execute the supplied content scripts, and load any supplied stylesheets, in the context of any documents matching the pattern specified by the include property.
...once destroyed the page-mod can no longer be used.

ui/frame - Archive of obsolete content
once created, the frame needs to be added to a toolbar for it to be visible: var { frame } = require("sdk/ui/frame"); var { toolbar } = require("sdk/ui/toolbar"); var frame = new frame({ url: "./frame.html" }); var toolbar = toolbar({ name: "my-toolbar", title: "my toolbar", items: [frame] }); parameters options : object required options: name type url u...
... once(event, listener) assign a listener to the first occurrence only of an event emitted by the frame.
... var { frame } = require("sdk/ui/frame"); var frame = new frame({ url: "./frame.html" }); frame.once("message", pong) function pong(e) { if (e.data == "ping") { // message only the sender, and not any frames attached to other browser windows e.source.postmessage("pong", "*"); } } parameters event : string the name of the event to listen to.
...for example, this code is equivalent to once(): var { frame } = require("sdk/ui/frame"); var frame = new frame({ url: "./frame.html" }); frame.on("message", pong) function pong(e) { if (e.data == "ping") { e.source.postmessage("pong", "*"); } frame.removelistener("message", pong) } parameters event : string the event the listener is listening for.

Creating custom Firefox extensions with the Mozilla build system - Archive of obsolete content
focus on the fact that once you get the build working, it'll probably work effortlessly from then on.
...personally i would discourage this practice (among other things, static linking means the same code gets loaded more than once into memory, and the code won't be available from javascript or other non-c++ languages) and encourage the use of xpcom wherever possible.
... once you've written the necessary chrome files (for instance, an overlay that adds a menu item to instantiate and use one of your components), you need to package them up as part of your extension.
...the only file that really stays put is install.rdf, which still exists once and only once in the extension root directory.

How to convert an overlay extension to restartless - Archive of obsolete content
branch : services.prefs; branch.setcomplexvalue(prefname, components.interfaces.nsisupportsstring, string); } just grab the above, move your default preferences file to your chrome mapping, and then do the following line once during your startup: services.scriptloader.loadsubscript("chrome://myaddon/content/defaultprefs.js", {pref:setdefaultpref} ); that's it.
... once you've got the machinery to load and save preferences without having to jump through the various pref type hoops the actual preferences api sends you through, loading the actual preferences file is one line.
... step 5: no more internal jar files you know how i've been mentioning extractionless add-ons every once in a while thus far?
... also note that once you do get this all up and running, your users will still have to restart firefox once to install your first restartless update.

Chapter 5: Let's build a Firefox extension - Archive of obsolete content
preference description value nglayout.debug.disable_xul_cache (not present in firefox 3.5+) ordinarily, firefox will cache xul documents after they have been read in once, to speed subsequent displays.
...the files clock.xul and clock.js will be read in every time you open the clock window, so just re-opening the clock window once will suffice to check them.
...because we’ve changed the chrome manifest, we need to relaunch firefox once, as discussed in the part “operations checks on revised source files”.
...once you’ve reinstalled it, first open about:config, and confirm that the previous preference values are set.

Local Storage - Archive of obsolete content
others feel concerned about privacy and storing private information locally without deleting it.
...if you need a complex database this can be heavy in terms of time and code, but this will only happen once and this can be done in a lazy or asynchronous way.
...they allow you to automatically generate xul content using information from a datasource, and automatically update the content once the datasource changes.
...there's a section about sqlite templates in the guide, but there are some concepts in it that will require you to read at least some of the rest of it.

Adding preferences to an extension - Archive of obsolete content
as before, concepts covered in the previous articles in this series won't be rehashed here, so if you haven't already seen them: creating a status bar extension creating a dynamic status bar extension also, for reference, you may want to take a look at preferences system and the preferences api.
... once we've established that the event is in fact a preference change, we look at the data parameter, which contains the name of the preference that changed.
... once we've gotten the updated preference, we call refreshinformation() to immediately update the display with the new stock's information.
... once we have the symbol in the local variable symbol, we use that to construct the url and the string to display in the status bar panel.

Bookmark Keywords - Archive of obsolete content
once that's done, all it takes to go to the cnn home page would be to type <tt>cnn</tt> into the address bar.
...once you get a result page, bookmark that page.
... once this result page has been bookmarked, we need only adjust the boookmark's properties.
...once that's been done, making the keymark work is a simple matter of going into the bookmark manager and adding a keyword!

How to Write and Land Nanojit Patches - Archive of obsolete content
once the patch seems ready, copy it to the other two repositories and test it.
... but don't push that update, as that should only be done by a member of that public repo.] once it passes testing, file the patch to bugzilla (file a bug under the "nanojit" component in the "core" product) and get a review.
...once it passes review, land it on nanojit-central, mark the bug's whiteboard as fixed-in-nanojit, and note the revision in a comment.
...once all the patches pass review, land the nanojit patch on nanojit-central and mark the bug as fixed-in-nanojit.

The new nsString class implementation (1999) - Archive of obsolete content
nscstring same as nsstring, but should be used with caution because of localization concerns.
...i18n issues another concern (mainly of the i18n team) has to do with the use of a 1-byte (ascii) nscstring at all.
...here's it's api: class nsimemoryagent : nsisupports { void* new(nsint32 asize)=0; //used for both alloc and realloc void* delete(void* aptr)=0; }; internationalization the new nsstrimpl/nsstring implementation addresses at least two of the primary concerns of our i18n team.
...second, they are concerned that programmers be prevented from abusing the string classes in a number of ways.

Building accessible custom components in XUL - Archive of obsolete content
<code> <window id="accjax" title="accjax spreadsheet" xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul" xmlns:x2="http://www.w3.org/tr/xhtml2" xmlns:wairole="http://www.w3.org/2005/01/wai-rdf/guiroletaxonomy#" > </code> once the namespaces are in place, we define the roles for each component of our spreadsheet.
...my#" xmlns:waistate="http://www.w3.org/2005/01/wai-rdf/guistatetaxonomy#" onload="install_handlers()" > <script src="accjax.js"/> </code> by adding this javascript code and these css rules, we can tab to the spreadsheet see which cell, row header, or column header has focus click on other cells or headers to change focus within the spreadsheet tab off the spreadsheet by pressing tab once tab back to the spreadsheet and automatically set focus to the previously focused cell or header inspect32 confirms that all of this really works; it's not just visual smoke and mirrors.
... <caption>editing a cell</caption> once we're satisfied with our changes, we can press enter again to accept the value.
...note that the role is once again "cell", since we explicitly set it when we recreated the label element.

PopupEvents - Archive of obsolete content
popupshown this event is fired on a menupopup, panel or tooltip once it is visible on screen.
... popuphiding this event is fired on a menupopup, panel or tooltip once it is about to be hidden.
... popuphidden this event is fired on a menupopup, panel or tooltip once it has been hidden.
...the popupshown event the popupshown event is fired once a popup is already visible.

Result Generation - Archive of obsolete content
once you have selected a starting point, you use a number of statements which indicate where to go next when navigating the graph.
...once all results have been examined, the builder moves on to the next statement in the query.
... once all statements have been analyzed, any results which still remain go on to become matches.
...so, to summarize: start out with a one possible result as the seed iterate over the results determined so far and augment them with additional data add any new possible results remove any rejected results repeat steps 2 to 4 for each query statement once done, all remaining results become matches each possible result is made up of a set of variable-value pairs.

Audio for Web games - Game development
note: in many ways the concept of buffering is an outdated one.
...once you have the various tracks that make up your piece you can bring tracks in and out as appropriate.
... once they are available to play, we need to make sure they start at the correct point that other tracks might be playing at, so they sync up.
... let's create another async function to set up the sample — we can combine the two async functions in a nice promise pattern to perform further actions when each file is loaded and buffered: async function loadfile(filepath) { const track = await getfile(filepath); return track; } let's also create a playtrack() function, which we can call once a file has been fetched.

Extra lives - Game development
add the ballleavescreen() function definition at the end of our code: function ballleavescreen() { lives--; if(lives) { livestext.settext('lives: '+lives); lifelosttext.visible = true; ball.reset(game.world.width*0.5, game.world.height-25); paddle.reset(game.world.width*0.5, game.world.height-5); game.input.ondown.addonce(function(){ lifelosttext.visible = false; ball.body.velocity.set(150, -150); }, this); } else { alert('you lost, game over!'); location.reload(); } } instead of instantly printing out the alert when you lose a life, we first subtract one life from the current number and check if it's a non-zero value.
... events you have probably noticed the add() and addonce() method calls in the above two code blocks and wondered how they differ.
... the difference is that the add() method binds the given function and causes it to be executed every time the event occurs, while addonce() is useful when you want to have the bound function executed only once and then unbound so it is not executed again.
... in our case, on every outofbounds event the ballleavescreen will be executed, but when the ball leaves the screen we only want to remove the message from the screen once.

HTML: A good basis for accessibility - Learn web development
if you try our longer version out with a screen reader (see bad-semantics.html), you'll not have a very good experience — the screen reader hasn't got anything to use as signposts, so you can't retrieve a useful table of contents, and the whole page is seen as a single giant block, so it is just read out in one go, all at once.
... expand acronyms, at least once or twice.
...in this section, we'll look at the basic accessibility concerns to be aware of when creating such controls.
... people experiencing low vision conditions, who are navigating with the aid of screen reading technology, or who have cognitive concerns may become confused when the new tab, window, or application is opened unexpectedly.

HTML: A good basis for accessibility - Learn web development
if you try our longer version out with a screen reader (see bad-semantics.html), you'll not have a very good experience — the screen reader hasn't got anything to use as signposts, so you can't retrieve a useful table of contents, and the whole page is seen as a single giant block, so it is just read out in one go, all at once.
... expand acronyms, at least once or twice.
...in this section, we'll look at the basic accessibility concerns to be aware of when creating such controls.
... people experiencing low vision conditions, who are navigating with the aid of screen reading technology, or who have cognitive concerns may become confused when the new tab, window, or application is opened unexpectedly.

Accessible multimedia - Learn web development
nds = math.floor(player.currenttime - minutes * 60); let minutevalue; let secondvalue; if (minutes<10) { minutevalue = "0" + minutes; } else { minutevalue = minutes; } if (seconds<10) { secondvalue = "0" + seconds; } else { secondvalue = seconds; } mediatime = minutevalue + ":" + secondvalue; timelabel.textcontent = mediatime; }; each time the time updates (once per second), we fire this function.
...for example, some users may not be able to hear the audio because they are in noisy environments (like a crowded bar when a sports game is being shown) or might not want to disturb others if they are in a quiet place (like a library.) this is not a new concept — television services have had closed captioning available for quite a long time: whereas many countries offer english films with subtitles written in their own native languages, and different language subtitles are often available on dvds, for example there are different types of text track with different purposes.
...you might also need to deal with games, animations, slideshows, embedded video, and content created using other available technologies such as: html5 canvas flash silverlight for such content, you need to deal with accessibility concerns on a case by case basis.
... summary this chapter has provided a summary of accessibility concerns for multimedia content, along with some practical solutions.

Organizing your CSS - Learn web development
this can make it easier to keep your css organised, and also means that if multiple people are working on the css you will have fewer situations where two people need to work on the same stylesheet at once, leading to conflicts in source control.
... oocss most of the approaches that you will encounter owe something to the concept of object oriented css (oocss), an approach made popular by the work of nicole sullivan.
... $base-color: #c6538c; .alert { border: 1px solid $base-color; } once compiled to css, you would end up with the following css in the final stylesheet.
... post-processing for optimization if you are concerned about adding size to your stylesheets by adding a lot of additional comments and whitespace for example, then a post-processing step could be to optimize the css by stripping out anything unnecessary in the production version.

Introduction to CSS layout - Learn web development
overview: css layout next this article will recap some of the css layout features we've already touched upon in previous modules — such as different display values — and introduce some of the concepts we'll be covering throughout this module.
...the fact that you can change the value of display for any element means that you can pick html elements for their semantic meaning, without being concerned about how they will look.
... once again, you can switch on grid layout with a specific value of display — display: grid.
...0); padding: 1em; } .wrapper { display: grid; grid-template-columns: 1fr 1fr 1fr; grid-template-rows: 100px 100px; grid-gap: 10px; } <div class="wrapper"> <div class="box1">one</div> <div class="box2">two</div> <div class="box3">three</div> <div class="box4">four</div> <div class="box5">five</div> <div class="box6">six</div> </div> once you have a grid, you can explicitly place your items on it, rather than relying on the auto-placement behavior seen above.

Fundamental text and font styling - Learn web development
once it reaches the end, it goes down to the next line and continues, then the next line, until all the content has been placed in the box.
...it is quite natural once you get used to it, and you can use em to size everything, not just text.
... you should note that text-decoration can accept multiple values at once, if you want to add multiple decorations simultaneously, for example text-decoration: underline overline.
...once you've become used to using the above, you should also explore the following: font styles: font-variant: switch between small caps and normal font alternatives.

Learn to style HTML using CSS - Learn web development
in that module, you will learn about: css, starting with the introduction to css module more advanced html modules javascript, and how to use it to add dynamic functionality to web pages once you understand the fundamentals of html, we recommend that you learn html and css at the same time, moving back and forth between the two topics.
... styling text with the basics of the css language covered, the next css topic for you to concentrate on is styling text — one of the most common things you'll do with css.
...but there's not much you can't do once you have a solid understanding of even the basics of css.
... one of the best things about learning css is that once you know the fundamentals, usually you have a pretty good feel for what can and can't be done, even if you don't actually know how to do it yet!

Other form controls - Learn web development
in both cases the interaction is the same — once the control is activated, the browser displays a list of values the user can select between.
...ion selected>cherry</option> <option>lemon</option> </optgroup> <optgroup label="vegetables"> <option>carrot</option> <option>eggplant</option> <option>potato</option> </optgroup> </select> note: in the case of multiple choice select boxes, you'll notice that the select box no longer displays the values as drop-down content — instead, all values are displayed at once in a list, with the optional size attribute determining the height of the widget.
... once a data list is affiliated with a form widget, its options are used to auto-complete text entered by the user; typically, this is presented to the user as a drop-down box listing possible matches for what they've typed into the input.
...you don't need to remember all of these details at once, and can return to these articles as often as you like to check up on details.

Document and website structure - Learn web development
we use color and font size to draw sighted users' attention to the most useful parts of the content, like the navigation menu and related links, but what about visually impaired people for example, who might not find concepts like "pink" and "large font" very useful?
...use <main> only once per page, and put it directly inside <body>.
...for example: <p>there once was a man named o'dell<br> who loved to write html<br> but his structure was bad, his semantics were sad<br> and his markup didn't read very well.</p> without the <br> elements, the paragraph would just be rendered in one long line (as we said earlier in the course, html ignores most whitespace); with <br> elements in the code, the markup renders like this: <hr> elements create a horizontal ...
...he read it hazily and sighed; "better get back to work then", he mused.</p> would render like this: planning a simple website once you've planned out the structure of a simple webpage, the next logical step is to try to work out what content you want to put on a whole website, what pages you need, and how they should be arranged and link to one another for the best possible user experience.

From object to iframe — other embedding technologies - Learn web development
there are some serious security concerns to consider with <iframe>s, as we'll discuss below, but this doesn't mean that you shouldn't use them in your websites — it just requires some knowledge and careful thinking.
...this makes your page usable sooner and decreases your official page load time (an important seo metric.) security concerns above we mentioned security concerns — let's go into this in a bit more detail now.
... we are not expecting you to understand all of this content perfectly the first time; we just want to make you aware of this concern, and provide a reference to come back to as you get more experienced and start considering using <iframe>s in your experiments and work.
... the case against plugins once upon a time, plugins were indispensable on the web.

Choosing the right approach - Learn web development
failure callbacks need to be called once for each level of nesting, whereas with promises you can just use a single .catch() block to handle the errors for the entire chain.
...we then run it once per second using setinterval(), creating the effect of a digital clock that updates once per second (see this live, and also see the source): function displaytime() { let date = new date(); let time = date.tolocaletimestring(); document.getelementbyid('demo').textcontent = time; } const createclock = setinterval(displaytime, 1000); pitfalls the frame rate isn't optimized for the sy...
...if you want to use async/await but are concerned about older browser support, you could consider using the babeljs library — this allows you to write your applications using the latest javascript and let babel figure out what changes if any are needed for your user’s browsers.
... further information making asynchronous programming easier with async and await async function reference await operator reference previous overview: asynchronous in this module general asynchronous programming concepts introducing asynchronous javascript cooperative asynchronous javascript: timeouts and intervals graceful asynchronous programming with promises making asynchronous programming easier with async and await choosing the right approach ...

Introducing asynchronous JavaScript - Learn web development
once the alert is dismissed, we create a <p> element.
...in essence, it's the browser's way of saying "i promise to get back to you with the answer as soon as i can," hence the name "promise." this concept can take practice to get used to; it feels a little like schrödinger's cat in action.
... only once the fetch() block has completely finished running and delivering its result through the .then() blocks will we finally see the second console.log() message (it worked :)) appear.
... previous overview: asynchronous next in this module general asynchronous programming concepts introducing asynchronous javascript cooperative asynchronous javascript: timeouts and intervals graceful asynchronous programming with promises making asynchronous programming easier with async and await choosing the right approach ...

Looping code - Learn web development
as well as being associated with popular breakfast cereals, roller coasters, and musical production, they are also a critical concept in programming.
... at this point, you probably understand the high-level concepts behind loops, but you are probably thinking "ok, great, but how does this help me write better javascript code?" as we said earlier, loops are all to do with doing the same thing over and over again, which is great for rapidly completing repetitive tasks.
...in a do...while loop, the code inside the curly braces is always run once before the check is made to see if it should be executed again (in while and for, the check comes first, so the code might never be executed).
... conclusion this article has revealed to you the basic concepts behind, and different options available when looping code in javascript.

Drawing graphics - Learn web development
the code for the loop that keeps everything moving looks like this: function loop() { ctx.fillstyle = 'rgba(0, 0, 0, 0.25)'; ctx.fillrect(0, 0, width, height); for(let i = 0; i < balls.length; i++) { balls[i].draw(); balls[i].update(); balls[i].collisiondetect(); } requestanimationframe(loop); } loop(); we run the loop() function once at the bottom of the code to start the cycle, drawing the first animation frame; the loop() function then takes charge of calling requestanimationframe(loop) to run the next frame of the animation, again and again.
...once you've drawn a graphic to a canvas, there's no way to manipulate that graphic individually like you can with dom elements.
... you can't move each ball around on the canvas, because once it's drawn, it's part of the canvas, and is not an individual accessible element or object.
... at the bottom of the javascript, add the following line to once again make the coordinate origin sit in the middle of the canvas: ctx.translate(width/2, height/2); now let's create a new htmlimageelement object, set its src to the image we want to load, and add an onload event handler that will cause the draw() function to fire when the image is loaded: let image = new image(); image.src = 'walk-right.png'; image.onload = draw; now we'll add...

Storing the information you need — Variables - Learn web development
initializing a variable once you've declared a variable, you can initialize it with a value.
... updating a variable once a variable has been initialized with a value, you can change (or update) that value by simply giving it a different value.
...try entering the following lines into your console: let mynamearray = ['chris', 'bob', 'jim']; let mynumberarray = [10, 15, 40]; once these arrays are defined, you can access each value by their location within the array.
... constants in javascript many programming languages have the concept of a constant — a value that once declared can't be changed.

Server-side web frameworks - Learn web development
don't be concerned if it doesn't all make sense now; we'll be working you through the code in our framework-specific modules.
... productivity: productivity is a measure of how quickly you can create new features once you are familiar with the framework, and includes both the effort to write and maintain code (since you can't write new features while old ones are broken).
... scalability: once your website is fantastically successful you will exhaust the benefits of caching and even reach the limits of vertical scaling (running your web application on more powerful hardware).
...it similarly encourages the use of design patterns like dry ("dont repeat yourself" — write code only once if at all possible), mvc (model-view-controller) and a number of others.

Framework main features - Learn web development
typescript is not concerned with the writing of user interfaces, but it is a domain-specific language, and has significant differences to vanilla javascript.
... </figcaption> </figure> state we talked about the concept of state in the previous chapter — a robust state-handling mechanism is key to an effective framework, and each component may have data to control the state of.
... import authorcredit from "./components/authorcredit"; once that’s done, authorcredit could be used inside the article component like this: ...
... this diagram of a react component's lifecycle offers a general overview of the concept.

Handling common accessibility problems - Learn web development
hiding content there are many instances where a visual design will require that not all content is shown at once.
... note: you should go through the tutorial at least once — it is a really useful way to learn vo.
... vo + shift + down cursor move into a group of items (such as an html table, or a form, etc.) once inside a group you can move around and select items inside that group using the above commands as normal.
... once downloaded, install it — you double click the installer, accept the license and follow the prompts.

Implementing feature detection - Learn web development
objective: to understand what the concept of feature detection is, and be able to implement suitable solutions in css and javascript.
... the concept of feature detection the idea behind feature detection is that you can run a test to determine whether a feature is supported in the current browser, and then conditionally run code to provide an acceptable experience both in browsers that do support the feature, and browsers that don't.
...we first use the media attribute to only apply the brick css to the page if the page width is 480px or less: <link href="dist/brick.css" type="text/css" rel="stylesheet" media="all and (max-width: 480px)"> we then use matchmedia() in the javascript several times, to only run brick navigation functions if we are on the small screen layout (in wider screen layouts, everything can be seen at once, so we don't need to navigate between different views).
... summary this article covered feature detection in a reasonable amount of detail, going through the main concepts and showing you how to both implement your own feature detection tests and use the modernizr library to implement tests more easily.

Handling common HTML and CSS problems - Learn web development
first things first: fixing general problems we said in the first article of this series that a good strategy to begin with is to test in a couple of modern browsers on desktop/mobile, to make sure your code is working generally, before going on to concentrate on the cross browser issues.
... once you've identified a list of potential problem technologies you will be using, it is a good idea to research what browsers they are supported in, and what related techniques are useful.
... once you've found out which prefixes you need to support, you should write them all out in your css, for example: -ms-transform: rotate(90deg); -webkit-transform: rotate(90deg); transform: rotate(90deg); this ensures that all browsers that support any of the above forms of the property can make the feature work.
...for example, you can use it with a task runner/build tool such as gulp or webpack to automatically add prefixes once development has been done.

Command line crash course - Learn web development
once you are finished looking through the man page, you need to quit out of it using your text viewer’s quit command ("q" in less; you may have to search on the web to find it if it isn’t obvious).
...this allows you to run an operation against a potentially large number of files at once, all of which match the specified pattern.
... there's pros and cons each way — and this list of pros and cons for globally installing is far from exhaustive: pros of installing globally cons of installing globally accessible anywhere in your terminal may not be compatible with your project's codebase only install once other developers in your team won't have access to these tools, for example if you are sharing the codebase over a tool like git.
... once you've installed node, open up the terminal and run the following command to install prettier: npm install --global prettier once the command has finished running, the prettier tool is now available in your terminal, at any location in your file system.

Adding a new CSS property
once you know which struct you're going to use (or that the property is a shorthand), you can add appropriate entry to nscssproplist.h.
... (note that when the longhand property css_property_parse_value_list, the shorthand property parser would be assumed to be reusing the longhand parser once per item, not for a whole list, as for properties like background-image or transform-timing-function.) if the property takes a list of keywords other than inherit/initial/etc., auto, none, or normal (which can be expressed using the variant_* flags), you should use variant_keyword and add a keyword table to the nscssprops class.
... this line describes the conceptual representation (but not syntax) of the computed value of the property.
... the data structures in gecko that store the computed value must correspond to this concept, or inheritance won't work as described by the specification.

How Mozilla's build system works
the contents below will explain the basic concepts and terminology of the build system and how to do common tasks such as compiling components and creating jar files.
... phase 2: build backend preparation and the build definition once configure has determined what the current build configuration is, we need to apply this to the source tree so we can actually build.
... one concept you will need be familiar with is variables in make.
...for example, you could have: dirs = \ public \ resources \ src \ $(null) this example demonstrates another concept called continuation lines.

Multiple Firefox profiles
it takes little time to set up a new profile, and once it is complete, all of your firefox versions will update separately and can be run simultaneously.
... once you are all done, click ok.
...once done, each one should automatically start with the specified profile.
...once you get to the point of adding a new item, you can have the profile dialog show up every time or set the launcher to launch a specific profile.

Performance
performance best practices declaring stateless functions once per process bad: // addon.js services.mm.loadframescript("framescript.js", true) // framescript.js const precomputedconstants = // ...
...omething(message) { frameglobal = message.target result = helper(frameglobal.content, message.data) frameglobal.sendasyncmessage("my-addon:response-from-child", {something: result}) } function addframe(frameglobal) { frameglobal.addmessagelistener("my-addon:request-from-parent", dosomething) } javascript modules are per-process singletons and thus all their objects are only initialized once, which makes them suitable for stateless callbacks.
... store heavyweight state once per process bad: // addon.js var main = new myaddonservice(); main.onchange(statechange); function statechange() { services.mm.broadcastasyncmessage("my-addon:update-configuration", {newconfig: main.serialize()}) } // framescript.js var maincopy; function onupdate(message) { maincopy = myaddonservice.deserialize(message.data.newconfig); } addmessagelistener("my-addon:update-configuration", onupdate) // maincopy used by other functions the main issue here is that a separate object is kept for each tab.
... better: content-document-global-created notifications can be substituted with domwindowcreated events other observers and services should be registered in a process script or jsm instead load frame scripts on demand bad: // addon.js services.mm.loadframescript("framescript.js", /*delayed:*/ true) // stuff communicating with the framescript // framescript.js function onlyonceinabluemoon() { // we only need this during a total solar eclipse while goat blood rains from the sky sendasyncmessage('my-addon:paragraph-count', {num: content.document.queryselectorall('p').length}) } addmessagelistener("my-addon:request-from-parent", onlyonceinabluemoon) better: // addon.js function ontoolbarbutton(event) { let tabmm = gbrowser.mcurrentbrowser.frameloader.messagemana...

Message manager overview
process scripts are most likely to be useful when chrome code wants to run some code only once in the content process, to access some global service: for example, to register an observer or a content policy.
...multiprocess firefox has the concept of: a "parent process" "child processes" which are processes spawned by the parent process.
...this is the recommended way to load a script that executes just once per child process, which is something you might want to do if you are interacting with some global service (for example, adding listeners to observer notifications or registering components).
...since javascript modules are singletons they will only be executed once per process even when they are loaded in multiple frame scripts.

Performance best practices for Firefox front-end engineers
this allows you to put all of your dom writes (most importantly, anything that could change the size or position of things in the dom) just before the style and layout steps of the pipeline, combining all the style and layout calculations into a single batch so it all happens once, in a single frame tick, instead of across multiple frames.
...once the styles have been calculated, we then need to calculate where things are going to be placed on the page.
... once the fragment is populated, append the fragment to the dom by calling appendchild() on the parent element for the new elements.
... consider loading scripts with the subscript loader asynchronously if you've ever used the subscript loader, you might not know that it can load scripts asynchronously, and return a promise once they're loaded.

Overview of Mozilla embedding APIs
currently, once gecko has been shutdown, it cannot be restarted in the same process space...
...conceptually, each nswebbrowser instance represents a html content area.
... conceptually, for each document being rendered, gecko creates a container called a domwindow.
...once all of the options have been set, the nsiwebbrowserprint interface is used to print the contents of the desired domwindow.

How to get a stacktrace with WinDbg
once the download is complete, you need to configure windbg to examine child processes, ignore a specific event caused by flash player, and record a log of loaded modules.
... .logopen /t c:\temp\firefox-debug.log .childdbg 1 .tlist sxn gp lm if you see firefox.exe listed in the output from .tlist more than once, then you are already running the application and need to close the running instance first before you start debugging, otherwise you won't get useful results.
... once the browser crashes, you will see an error (such as "access violation") in the windbg command window.
...once the browser has crashed or been stopped, continue with the steps below.

Localizing with Mercurial
once you've installed mercurial, we'll walk through the steps to configure it.
... configuring mercurial once you've installed mercurial, you'll need to configure it before you can use it successfully.
... once you finish making your change, run hg qrefresh to commit your changes to the patch.
...for peers of a localization, the owner can vouch (once she or he is registered).

Localizing without a specialized tool
this directory structure needs to mimic the same as the en-us source files concerning localization.
... you can always check the path by typing pwd once you are in the root working directory with both en-us source and the l10n base, copy the searchbar.dtd file by typing cp mozilla-1.9.2/browser/locales/chrome/browser/searchbar.dtd l10n-mozilla-1.9.2/x-testing/browser/chrome/browser/ open the file in your x-testing directory and translate the words inside the quotation marks.
... you can always check the path by typing pwd once you are in the root working directory with both en-us source and the l10n base, copy the searchbar.dtd file by typing cp mozilla-1.9.2/browser/locales/chrome/browser/search.properties l10n-mozilla-1.9.2/x-testing/browser/chrome/browser/ open that file and translate the strings that follow the "=".
...untrusted connection in the example above), like so (example for polish): <!entity certerror.pagetitle "niezaufane połączenie"> once you have translated all the <!entity> strings in this file, you should save your work and open the next .dtd or .properties file.

Localization technical reviews
that being the case, there are some criteria in a technical review that will only ever be considered once, as all reviews after this only evaluate the changes you're adding on top of this revision from release to release.
...once attached, open the attachment details.
...once they are fixed, push your fix to your repo, attach it to the corresponding bug using the same mercurial revision number as before, and then request another review.
... once your work is entirely approved, go out and celebrate!

About NSPR
the first generation of nspr was originally conceived just to satisfy the requirements of porting java to various host environments.
...(the "20" in "nspr20" does not mean "version 2.0" but rather "second generation".) many of the concepts have been reformed, expanded, and matured.
...the operating systems provide everything from no concept of threading at all up to and including sophisticated, scalable and efficient implementations.
...hoare in monitors: an operating system structuring concept , communications of the acm, 17(10), october 1974 and then formalized by xerox' mesa programming language ("mesa language manual", j.g.

Introduction to NSPR
this chapter introduces key nspr programming concepts and illustrates them with sample code.
... locks and monitors in general, a monitor is a conceptual entity composed of a mutex, one or more condition variables, and the monitored data.
... note: evaluation of the invariant expression is a conceptual requirement and is rarely done in practice.
...once the lock primitive is called, the thread returns only when it has acquired the lock.

Web Replay
the middleman can spawn multiple child processes at once, and coordinate their behavior so they run in parallel.
... there can be up to one recording child and two replaying children at once.
... once all thread are idle, the main thread computes the memory diff, reads the stacks from each thread and their register state (which each thread recorded by calling setjmp before idling).
...:bhackett on bugzilla with any questions or concerns.

Finishing the Component
once you have these interface and header files, you can modify the weblock class to implement the nsicontentpolicy interface.
... once you have made sure that your component builds with the new header file, you must derive the weblock class from the interface nsicontentpolicy, which you can do by simply adding a public declaration when defining the class.
...the code for getting the io service from the service manager looks like this: // get a pointer to the ioservice rv = servman->getservicebycontractid("@mozilla.org/network/io-service;1", ns_get_iid(nsiioservice), getter_addrefs(mioservice)); once you have this interface pointer, you can easily create nsiuri objects from a string, as in the following snippet: nscomptr<nsiuri> uri; nsembedcstring urlstring(node->urlstring); mioservice->newuri(urlstring, nsnull, nsnull, getter_addrefs(uri)); this code wraps a c-string with a nsembedcstring, which you'll recall is a string class that...
... once the url string is wrapped in a nsembedcstring, it can be passed to the method newuri.

Packaging WebLock
once you have the component and the other resources for weblock packaged properly (see the following section, archiving resources), the installation script for weblock is a simple one (see the weblock installation script).
... archiving resources once you have compiled all the resources that make up the weblock component and the files that make up the user interface that will be added to the browser, you can place these within a subdirectory called weblock.
...once triggered (see the weblock trigger script), the installation script: downloads the weblock component and places it in the components directory copies the weblock subdirectory in the mozilla chrome application subdirectory registers both the component and the ui the xpinstall api provides such essential methods[essential-methods] as initinstall, registerchrome, addfile, and others.
...lation</title> <script> /* * trigger function that downloads the xpi so the * install.js file inside can be read and executed */ function installweblock() { weblock_xpi = {'weblock extension': 'weblock.xpi'}; installtrigger.install(weblock_xpi); } </script> <h1>install weblock</h1> <p><a href="#" onclick="installweblock();">install weblock</a></p> </html> distributing your component once you have the component packaged properly and the necessary installation and trigger scripts, you are ready to distribute your component so others can install it in their gecko applications.

nsIScriptableInputStream
note: the close method may be called more than once, but subsequent calls are ignored.
...note: the init method may be called more than once, allowing a nsiscriptableinputstream instance to be reused.
...remember: the nsiscriptableinputstream has a contract where `init` should only be called once, and should always be closed.
...try(name); let stream = new scriptableinputstream(this.getinputstream(name)); try { // use readbytes to get binary data, read to read a (null-terminated) string let contents = stream.readbytes(entry.realsize); } finally { stream.close(); } example usage in ondataavailable remember: the nsiscriptableinputstream has a contract where `init` should only be called once, and should always be closed.

nsISocketTransport
note: this attribute cannot be changed once a stream has been opened.
... this attribute is only available once the socket is connected.
...this attribute is defined only once a connection has been established.
...this attribute is defined only once a connection has been established.

Filelink Providers
the button to set up the account will only become enabled once the checkvalidity method for the form returns true.
... once this is done, the field is accessible from within the implementation via the preferences api using the key mail.cloud_files.accounts.account_key.username where account_key is the value passed into the implementations init function.
... management interface once an account has been created, it is manageable from within the preferences dialog, in the attachment pane, in the outgoing tab.
... this function is called automatically once the dom content is done loading, and is passed a single parameter - the provider instance whose data is being displayed.

Add to iPhoto
once installed, when you right-click on an image, you'll see among the options in the contextual menu an option to "add image to iphoto".
...for example, the cfarray type describes an array, but cfarray objects can't be changed once they've been created.
... there's nothing particularly interesting about how we declare this api, but it will be noteworthy when we look at how we use cfmutablearray objects with methods that accept a cfarray as input, so i introduce this concept here.
...once we have the file, we start making use of our native apis.

Introduction to DOM Inspector - Firefox Developer Tools
using the dom inspector once you've opened the document for the page or chrome you are interested in, you'll see that it loads the dom nodes viewer in the document pane and the dom node viewer in the object pane.
... now, once you have selected a node like the "search-go-button" node, you can select any one of several viewers to display information about that node in the object pane of the dom inspector application window, all of which are available from the menupopup accessed from the upper left corner of the the object pane.
... loving the inspector the dom inspector can take some figuring out, but once you get used to it, you may find that these structured views of web pages and interfaces were exactly the aspects of your own application development that were missing.
...used in concert with mozilla tools like venkman, the javascript debugger, the dom inspector can give you a complete view of any web page or dom-based application interface.

Dominators - Firefox Developer Tools
this article provides an introduction to the concepts of reachability, shallow versus retained size, and dominators, as they apply in garbage-collected languages like javascript.
... these concepts matter in memory analysis, because often an object may itself be small, but may hold references to other much larger objects, and by doing this will prevent the garbage collector from freeing that extra memory.
...retained size is an important concept in analyzing memory usage, because it answers the question "if this object ceases to exist, what's the total amount of memory freed?".
... dominators a related concept is that of the dominator.

Applying styles and colors - Web APIs
// these all set the fillstyle to 'orange' ctx.fillstyle = 'orange'; ctx.fillstyle = '#ffa500'; ctx.fillstyle = 'rgb(255, 165, 0)'; ctx.fillstyle = 'rgba(255, 165, 0, 1)'; a fillstyle example in this example, we once again use two for loops to draw a grid of rectangles, each in a different color.
... for example: var lineargradient = ctx.createlineargradient(0, 0, 150, 150); var radialgradient = ctx.createradialgradient(75, 75, 0, 75, 75, 100); once we've created a canvasgradient object we can assign colors to it by using the addcolorstop() method.
...it's used only once.
...once we've created a pattern, we can assign it to the fillstyle or strokestyle properties.

Clipboard - Web APIs
all of the clipboard api methods operate asynchronously; they return a promise which is resolved once the clipboard access has been completed.
... readtext() requests text from the system clipboard; returns a promise which is resolved with a domstring containing the clipboard's text once it's available.
... writetext() writes text to the system clipboard, returning a promise which is resolved once the text is fully copied into the clipboard.
...due to both potential security concerns and technical complexities, the process of integrating this api is happening gradually in most browsers.

Traversing an HTML table with JavaScript and DOM Interfaces - Web APIs
once we have created the <table>, <tbody>, <tr>, and <td> elements, and then the text node, we then append each object to its parent in the opposite order: first, we attach each text node to its parent <td> element using cell.appendchild(celltext); next, we attach each <td> element to its parent <tr> element using row.appendchild(cell); next, we attach each <tr> element to the parent <tb...
... next, we get all the p elements that are descendants of the body: mybodyelements = mybody.getelementsbytagname("p"); finally, we get the second item from the list of p elements via myp = mybodyelements[1]; once you have gotten the dom object for an html element, you can set its properties.
... once you have the returned list, use [x] method to retrieve the desired child item.
...to retrieve the value of the attribute, use the getattribute method: mytable.getattribute("border"); hiding a column by changing style properties once you have the object in your javascript variable, you can set style properties directly.

EventTarget.addEventListener() - Web APIs
once a boolean indicating that the listener should be invoked at most once after being added.
... example of options usage html <div class="outer"> outer, once & none-once <div class="middle" target="_blank"> middle, capture & none-capture <a class="inner1" href="https://www.mozilla.org" target="_blank"> inner1, passive & preventdefault(which is not allowed) </a> <a class="inner2" href="https://developer.mozilla.org/" target="_blank"> inner2, none-passive & preventdefault(not open new page) </a> </div> </div> css .
...dth: 460px; } .inner1, .inner2 { border: 1px solid purple; color: purple; width: 400px; } javascript const outer = document.queryselector('.outer'); const middle = document.queryselector('.middle'); const inner1 = document.queryselector('.inner1'); const inner2 = document.queryselector('.inner2'); const capture = { capture : true }; const nonecapture = { capture : false }; const once = { once : true }; const noneonce = { once : false }; const passive = { passive : true }; const nonepassive = { passive : false }; outer.addeventlistener('click', oncehandler, once); outer.addeventlistener('click', noneoncehandler, noneonce); middle.addeventlistener('click', capturehandler, capture); middle.addeventlistener('click', nonecapturehandler, nonecapture); inner1.addeventlisten...
...er('click', passivehandler, passive); inner2.addeventlistener('click', nonepassivehandler, nonepassive); function oncehandler(event) { alert('outer, once'); } function noneoncehandler(event) { alert('outer, none-once, default'); } function capturehandler(event) { //event.stopimmediatepropagation(); alert('middle, capture'); } function nonecapturehandler(event) { alert('middle, none-capture, default'); } function passivehandler(event) { // unable to preventdefault inside passive event listener invocation.

Fetch API - Web APIs
concepts and usage fetch provides a generic definition of request and response objects (and other things involved with network requests).
... it also defines related concepts such as cors and the http origin header semantics, supplanting their separate definitions elsewhere.
... once a response is retrieved, there are a number of methods available to define what the body content is and how it should be handled (see body).
... note: find out more about using the fetch api features in using fetch, and study concepts in fetch basic concepts.

FileReader - Web APIs
filereader.readasarraybuffer() starts reading the contents of the specified blob, once finished, the result attribute contains an arraybuffer representing the file's data.
... filereader.readasbinarystring() starts reading the contents of the specified blob, once finished, the result attribute contains the raw binary data from the file as a string.
... filereader.readasdataurl() starts reading the contents of the specified blob, once finished, the result attribute contains a data: url representing the file's data.
... filereader.readastext() starts reading the contents of the specified blob, once finished, the result attribute contains the contents of the file as a text string.

Using the Gamepad API - Web APIs
once one gamepad has been interacted with, other gamepads that are connected will automatically be visible.
...we can use this in order to determine which gamepad (i.e., its id) had caused the event, since multiple gamepads might be connected at once.
...once we have a reference to it, we can query its properties for information about the current state of the gamepad.
...we have done this below using window.setinterval(); once the object is available the gamepad info is outputted, the game loop is started, and the interval is cleared using window.clearinterval().

Timing element visibility with the Intersection Observer API - Web APIs
finally, we set up an interval which triggers once a second to handle any necessary refreshing.
... handling intersection changes once per pass through the browser's event loop, each intersectionobserver checks to see if any of its target elements have passed through any of the observer's intersection ratio thresholds.
... handling periodic actions our interval handler, handlerefreshinterval(), is called about once per second courtesy of the call to setinterval() made in the startup() function described above.
... after that, the code paths converge once again.

Using the MediaStream Recording API - Web APIs
we'll concentrate on the recording and playback functionality for this article.
... the success callback: this code is run once the getusermedia call has been completed successfully.
... capturing the media stream once getusermedia has created a media stream successfully, you create a new media recorder instance with the mediarecorder() constructor and pass it the stream directly.
...first of all, mediarecorder.start() is used to start recording the stream once the record button is pressed: record.onclick = function() { mediarecorder.start(); console.log(mediarecorder.state); console.log("recorder started"); record.style.background = "red"; record.style.color = "black"; } when the mediarecorder is recording, the mediarecorder.state property will return a value of "recording".

Using the Notifications API - Web APIs
this is a common requirement when an api tries to interact with something outside a web page — at least once, the user needs to specifically grant that application permission to present notifications, thereby letting the user control which apps/sites are allowed to display notifications.
...if you want to support older versions, you might have to use the older callback version, which looks like this: notification.requestpermission(); the callback version optionally accepts a callback function that is called once the user has responded to the request to display permissions.
...most modern browsers dismiss notifications automatically after a few moments (around four seconds) but this isn't something you should generally be concerned about as it's up to the user and user agent.
... close triggered once the notification is closed.

PaymentRequest.show() - Web APIs
only one payment request can be in the process of being handled at once, across all documents.
... once one paymentrequest's show() method has been called, any other call to show() will by rejected with an aborterror until the returned promise has been concluded, either by being fulfilled with a paymentresponse indicating the results of the payment request, or by being rejected with an error.
... if your architecture doesn't necessarily have all of the data ready to go at the moment it instantiates the payment interface by calling show(), specify the detailspromise parameter, providing a promise that is fulfilled once the data is ready.
... the validateresponse() method, below, is called once show() returns, in order to look at the returned response and either submit the payment or reject the payment as failed: async function validateresponse(response) { try { if (await checkallvalues(response)) { await response.complete("success"); } else { await response.complete("fail"); } } catch(err) { await response.complete("fail"); } } here, a custom functi...

Using the Payment Request API - Web APIs
this takes two mandatory parameters and one option parameter: methoddata — an object containing information concerning the payment provider, such as what payment methods are supported, etc.
... details — an object containing information concerning the specific payment, such as the total payment amount, tax, shipping cost, etc.
...ortedtypes: ['debit', 'credit'] } }]; } function buildshoppingcartdetails() { // hardcoded for demo purposes: return { id: 'order-123', displayitems: [ { label: 'example item', amount: {currency: 'usd', value: '1.00'} } ], total: { label: 'total', amount: {currency: 'usd', value: '1.00'} } }; } starting the payment process once the paymentrequest object has been created, you call the paymentrequest.show() method on it to initiate the payment request.
...for example, redirect to // the legacy web form checkout: window.location.href = '/legacy-web-form-checkout'; }); // every click on the checkout button should use a new instance of // paymentrequest object, because paymentrequest.show() can be // called only once per instance.

RTCPeerConnection.setRemoteDescription() - Web APIs
the method takes a single parameter—the session description—and it returns a promise which is fulfilled once the description has been changed, asynchronously.
... return value a promise which is fulfilled once the value of the connection's remotedescription is successfully changed or rejected if the change cannot be applied (for example, if the specified description is incompatible with one or both of the peers on the connection).
... on the other hand, if we're in the middle of an ongoing negotiation and an offer is passed into setremotedescription(), the ice agent automatically begins an ice rollback in order to return the connection to a stable signaling state, then, once the rollback is completed, sets the remote description to the specified offer.
... pc.setremotedescription(sessiondescription, successcallback, errorcallback); parameters successcallback a javascript function which accepts no input parameters to be be called once the description has been successfully set.

Using writable streams - Web APIs
note: this article assumes that you understand the use cases of writable streams, and are aware of the high-level concepts.
... if not, we suggest that you first read the streams concepts and usage overview and dedicated streams api concepts article, then come back.
... the first object can contain up to four members, all of which are optional: start(controller) — a method that is called once, immediately after the writablestream is constructed.
... after the chunks have all been written, we then perform the ready check once more, to check that the last chunk has finished being written and all the work is done.

UIEvent.initUIEvent() - Web APIs
the uievent.inituievent() method initializes a ui event once it's been created.
...once dispatched, it doesn't do anything anymore.
...once set, the read-only property event.bubbles will give its value.
...once set, the read-only property event.cancelable will give its value.

A basic 2D WebGL animation example - Web APIs
once the shader program is built, we compute the aspect ratio of our context by dividing its width by its height.
... once the vertex array has been created, we create a new gl buffer to contain them by calling gl.createbuffer().
... once all of the shaders are compiled, the program is linked using gl.linkprogram().
... result this is a pretty simple example, since it's just drawing one simple object, but the concepts used here extend to much more complex animations.

WebGL model view projection - Web APIs
these matrices are core to moving data around on the screen, and are concepts that transcend individual frameworks and engines.
...ts multiplied by an additional projection matrix, which (as the name suggests) projects 3d points onto a 2d drawing surface: // make sure to read the transformations in reverse order gl_position = projection * model * vec4(position, 1.0); the results view on jsfiddle the viewing frustum before we move on to covering how to compute a perspective projection matrix, we need to introduce the concept of the viewing frustum (also known as the view frustum).
... once that's been done, we have the largest set of polygons which are entirely within the viewing frustum.
...urn [ f / aspectratio, 0, 0, 0, 0, f, 0, 0, 0, 0, (near + far) * rangeinv, -1, 0, 0, near * far * rangeinv * 2, 0 ]; } the four parameters into this function are: fieldofviewinradians an angle, given in radians, indicating how much of the scene is visible to the viewer at once.

Writing WebSocket client applications - Web APIs
the readystate will become open once the connection is ready to transfer data.
... if you want to open a connection and are flexible about the protocols you support, you can specify an array of protocols: var examplesocket = new websocket("wss://www.example.com/socketserver", ["protocolone", "protocoltwo"]); once the connection is established (that is, readystate is open), examplesocket.protocol will tell you which protocol the server selected.
... sending data to the server once you've opened your connection, you can begin transmitting data to the server.
...we can at least be sure that attempting to send data only takes place once a connection is established by defining an onopen event handler to do the work: examplesocket.onopen = function (event) { examplesocket.send("here's some text that the server is urgently awaiting!"); }; using json to transmit objects one handy thing you can do is use json to send reasonably complex data to the server.

Movement, orientation, and motion: A WebXR example - Web APIs
rendering the scene for immersive presentation requires multiple renders of the scene—once from the perspective of each eye.
...in either case, the label of the button is updated to indicate that a click will start a session, and then, if there is a pending request for an animation frame, we cancel it by calling cancelanimationframe once that's done, the value of xrsession is changed to null to indicate that we're done with the session.
...it's called once for each eye, with slightly different positions for each eye, in order to establish the 3d effect needed for xr gear.
...once they're compiled, the program is linked and returned to the caller.

Using the Web Audio API - Web APIs
we'll briefly look at some concepts, then study a simple boombox example that allows us to load an audio track, play and pause it, and change its volume and stereo panning.
... audio graphs everything within the web audio api is based around the concept of an audio graph, which is made up of nodes.
...our htmlmediaelement fires an ended event once it's finished playing, so we can listen for that and run code accordingly: audioelement.addeventlistener('ended', () => { playbutton.dataset.playing = 'false'; }, false); modifying sound let's delve into some basic modification nodes, to change the sound that we have.
...there's a lot more functionality to the web audio api, but once you've grasped the concept of nodes and putting your audio graph together, we can move on to looking at more complex functionality.

Web accessibility for seizures and physical reactions - Accessibility
this article introduces concepts behind making web content accessibile for those with vestibular disorders, and how to measure and prevent content leading to seizures and / or other physical reactions.
... additional concerns exist for individuals with motor-skills problems.
... a very old article, tech republic's epilepsy and crt/lcd screen flicker, had an interesting response concerning the refresh rates in hz.
...01ms !important; animation-iteration-count: 1 !important; /* hat tip nick/cssremedy (https://css-tricks.com/revisiting-prefers-reduced-motion-the-reduced-motion-media-query/#comment-1700170) */ transition-duration: 0.001ms !important; } } from w3.org's page on media queries 4: the update media feature is used to query the ability of the output device to modify the appearance of content once it has been rendered.

Layout using named grid lines - CSS: Cascading Style Sheets
once you work through some examples it should become clearer and easier to work with.
... .wrapper { display: grid; grid-template-columns: [main-start] 1fr [content-start] 1fr [content-end] 1fr [main-end]; grid-template-rows: [main-start] 100px [content-start] 100px [content-end] 100px [main-end]; } once the lines have names, we can use the name to place the item rather than the line number.
... * {box-sizing: border-box;} .wrapper { border: 2px solid #f76707; border-radius: 5px; background-color: #fff4e6; } .wrapper > div { border: 2px solid #ffa94d; border-radius: 5px; background-color: #ffd8a8; padding: 1em; color: #d9480f; } .wrapper { display: grid; grid-template-columns: repeat(12, [col-start] 1fr); } once you have created the grid you can place items onto it.
... .main-header, .main-footer { grid-column: col-start / span 12; } .side1 { grid-column: col-start / span 3; grid-row: 2; } .content { grid-column: col-start 4 / span 6; grid-row: 2; } .side2 { grid-column: col-start 10 / span 3; grid-row: 2; } once again, the grid highlighter is helpful to show us how the grid we have placed our items on works.

Relationship of grid layout to other layout methods - CSS: Cascading Style Sheets
once the browser has worked out how many times 200 pixels will fit into the container–also taking account of grid gaps–it will treat the 1fr maximum as an instruction to share out the remaining space between the items.
...once you have done this, if you give a grid item position: absolute it will take as its containing block the grid container or, if the item also has a grid position, the area of the grid it is placed into.
... once again the item no longer participates in the grid layout in terms of sizing or when other items are auto-placed.
... <div class="box box5">five</div> </div> .wrapper { display: grid; grid-template-columns: repeat(3, 1fr); grid-auto-rows: minmax(100px, auto); } .box1 { grid-column-start: 1; grid-column-end: 4; display: contents; } this can be a way to get items nested into the grid to act as if they are part of the grid, and is a way around some of the issues that would be solved by subgrids once they are implemented.

display - CSS: Cascading Style Sheets
please note that the css display level 3 spec defines how the contents value should affect "unusual elements" — elements that aren’t rendered purely by css box concepts such as replaced elements.
...see the accessibility concerns section below for more details.
... adapting to the new two-value syntax of display css flow layout (display: block, display: inline) block and inline layout in normal flow flow layout and overflow flow layout and writing modes formatting contexts explained in flow and out of flow display: flex basic concepts of flexbox aligning items in a flex container controlling ratios of flex items along the main axis cross-browser flexbox mixins mastering wrapping of flex items ordering flex items relationship of flexbox to other layout methods backwards compatibility of flexbox typical use cases of flexbox display: grid basic concepts of grid layout relationship to other layout methods line-ba...
...sed placement grid template areas layout using named grid lines auto-placement in grid layout box alignment in grid layout grids, logical values and writing modes css grid layout and accessibility css grid layout and progressive enhancement realizing common layouts using grids accessibility concerns display: none using a display value of none on an element will remove it from the accessibility tree.

WAI ARIA Live Regions/API Support - Developer guides
a state change event for the a11y api's busy state will be fired on the container object currently marked as busy, once it is no longer busy.
...the entire atomic region should be presented once when it is finally no longer busy.
... aria-busy on ancestor element container-atomic "true" | "false" "false" is this change inside a region that should always be presented at once.
...once the user presses the next key the speech will move on to echoing that key anyway.

Setting up adaptive streaming media sources - Developer guides
the good news is that once we have encoded our media in the appropriate format we are pretty good to go.
...seurl> </representation> <representation id="4" bandwidth="250000" width="480" height="360"> <baseurl>elephantsdream_h264bpl30_0250.264.dash</baseurl> </representation> <representation id="5" bandwidth="500000" width="480" height="360"> <baseurl>elephantsdream_h264bpl30_0500.264.dash</baseurl> </representation> </adaptationset> </period> </mpd> once you have generated your mpd file you can reference it from within the video tag.
... once encoded your file structure may look something like this: play list -> /segments/news.mp4.mpd main segment folder -> /segments/main/ 100 kbps segment folder -> /segments/main/news100 contains (1.m4s, 2.m4s, 3.m4s ...
... once you have generated your mpd file you can reference as expected it from within the <video> element: <video src="my.mpd" type="application/dash+xml"></video> it might be wise to provide a fallback: <video> <source src="my.mpd" type="application/dash+xml"> <!-- fallback --> <source src="my.mp4" type="video/mp4"> <source src="my.webm" type="video/webm"> </video> note: mpeg-dash playback ...

<input>: The Input (Form Input) element - HTML: Hypertext Markup Language
once one of the radio buttons in a group has focus, using the arrow keys will navigate through all the radio buttons of the same name, even if the radio buttons are not grouped together in the source order.
...the <label> element provides explanatory information about a form field that is always appropriate (aside from any layout concerns you have).
...not only is the placeholder not accessible to screen readers, but once the user enters any text into the form control, or if the form control already has a value, there is no placeholder.
... recommendation accessibility concerns labels when including inputs, it is an accessibilty requirement to add labels along side.

Using the application cache - HTML: Hypertext Markup Language
once all the files have been successfully retrieved, they are moved into the real offline cache automatically, and a cached event is sent to the applicationcache object.
...the wildcard character * can be used once.
... the cache, network, and fallback sections can be listed in any order in a cache manifest file, and each section can appear more than once in a single manifest.
... cache manifest files can switch from section to section at will (each section header can be used more than once), and sections are allowed to be empty.

Basics of HTTP - HTTP
http is an extensible protocol that relies on concepts like resources and uniform resource identifiers (uris), simple message structure, and client-server communication flow.
... on top of these basic concepts, numerous extensions have been developed over the years that add updated functionality and semantics with new http methods or headers.
... resources and uris a brief introduction to the concept of resources, identifiers, and locations on the web.
...this article explains both concepts.

CSP: child-src - HTTP
'nonce-<base64-value>' a whitelist for specific inline scripts using a cryptographic nonce (number used once).
... the server must generate a unique nonce value each time it transmits a policy.
... it is critical to provide an unguessable nonce, as bypassing a resource’s policy is otherwise trivial.
...specifying nonce makes a modern browser ignore 'unsafe-inline' which could still be set for older browsers without nonce support.

CSP: connect-src - HTTP
'nonce-<base64-value>' an allow-list for specific inline scripts using a cryptographic nonce (number used once).
... the server must generate a unique nonce value each time it transmits a policy.
... it is critical to provide an unguessable nonce, as bypassing a resource’s policy is otherwise trivial.
...specifying nonce makes a modern browser ignore 'unsafe-inline' which could still be set for older browsers without nonce support.

CSP: font-src - HTTP
'nonce-<base64-value>' a whitelist for specific inline scripts using a cryptographic nonce (number used once).
... the server must generate a unique nonce value each time it transmits a policy.
... it is critical to provide an unguessable nonce, as bypassing a resource’s policy is otherwise trivial.
...specifying nonce makes a modern browser ignore 'unsafe-inline' which could still be set for older browsers without nonce support.

CSP: frame-src - HTTP
'nonce-<base64-value>' a whitelist for specific inline scripts using a cryptographic nonce (number used once).
... the server must generate a unique nonce value each time it transmits a policy.
... it is critical to provide an unguessable nonce, as bypassing a resource’s policy is otherwise trivial.
...specifying nonce makes a modern browser ignore 'unsafe-inline' which could still be set for older browsers without nonce support.

CSP: manifest-src - HTTP
'nonce-<base64-value>' a whitelist for specific inline scripts using a cryptographic nonce (number used once).
... the server must generate a unique nonce value each time it transmits a policy.
... it is critical to provide an unguessable nonce, as bypassing a resource’s policy is otherwise trivial.
...specifying nonce makes a modern browser ignore 'unsafe-inline' which could still be set for older browsers without nonce support.

CSP: media-src - HTTP
'nonce-<base64-value>' a whitelist for specific inline scripts using a cryptographic nonce (number used once).
... the server must generate a unique nonce value each time it transmits a policy.
... it is critical to provide an unguessable nonce, as bypassing a resource’s policy is otherwise trivial.
...specifying nonce makes a modern browser ignore 'unsafe-inline' which could still be set for older browsers without nonce support.

CSP: object-src - HTTP
'nonce-<base64-value>' a whitelist for specific inline scripts using a cryptographic nonce (number used once).
... the server must generate a unique nonce value each time it transmits a policy.
... it is critical to provide an unguessable nonce, as bypassing a resource’s policy is otherwise trivial.
...specifying nonce makes a modern browser ignore 'unsafe-inline' which could still be set for older browsers without nonce support.

CSP: prefetch-src - HTTP
'nonce-<base64-value>' an allow-list for specific inline scripts using a cryptographic nonce (number used once).
... the server must generate a unique nonce value each time it transmits a policy.
... it is critical to provide an unguessable nonce, as bypassing a resource’s policy is otherwise trivial.
...specifying nonce makes a modern browser ignore 'unsafe-inline' which could still be set for older browsers without nonce support.

CSP: style-src-attr - HTTP
'nonce-<base64-value>' an allow-list for specific inline scripts using a cryptographic nonce (number used once).
... the server must generate a unique nonce value each time it transmits a policy.
... it is critical to provide an unguessable nonce, as bypassing a resource’s policy is otherwise trivial.
...specifying nonce makes a modern browser ignore 'unsafe-inline' which could still be set for older browsers without nonce support.

CSP: style-src-elem - HTTP
'nonce-<base64-value>' an allow-list for specific inline scripts using a cryptographic nonce (number used once).
... the server must generate a unique nonce value each time it transmits a policy.
... it is critical to provide an unguessable nonce, as bypassing a resource’s policy is otherwise trivial.
...specifying nonce makes a modern browser ignore 'unsafe-inline' which could still be set for older browsers without nonce support.

CSP: worker-src - HTTP
'nonce-<base64-value>' a whitelist for specific inline scripts using a cryptographic nonce (number used once).
... the server must generate a unique nonce value each time it transmits a policy.
... it is critical to provide an unguessable nonce, as bypassing a resource’s policy is otherwise trivial.
...specifying nonce makes a modern browser ignore 'unsafe-inline' which could still be set for older browsers without nonce support.

HTTP Index - HTTP
it relies on a few basic concepts like the notion of resources and uris, a simple structure of messages, and a client-server structure for the communication flow.
... on top of these basic concepts, numerous extensions have appeared over the years, adding new functionality and new semantics by creating new http methods or headers.
... 44 http conditional requests conditional requests, guide, http http has a concept of conditional requests, where the result, and even the success of a request, can be changed by comparing the affected resources with the value of a validator.
...several parts can be requested with one range header at once, and the server may send back these ranges in a multipart document.

Introduction - JavaScript
« previousnext » this chapter introduces javascript and discusses some of its fundamental concepts.
... where to find javascript information the javascript documentation on mdn includes the following: learn web development provides information for beginners and introduces basic concepts of programming and the internet.
...once you have a firm grasp of the fundamentals, you can use the javascript reference to get more details on individual objects and statements.
...you do not have to be concerned with whether methods are public, private, or protected, and you do not have to implement interfaces.

JavaScript modules - JavaScript
for example: export { name, draw, reportarea, reportperimeter }; importing features into your script once you've exported some features out of your module, you need to import them into your script to be able to use them.
... once you've imported the features into your script, you can use them just like they were defined inside the same file.
... modules are only executed once, even if they have been referenced in multiple <script> tags.
...once we turned off automatically hiding file extensions, and trained it to accept .mjs, it was ok.

Map.prototype.forEach() - JavaScript
the foreach() method executes a provided function once per each key/value pair in the map object, in insertion order.
... description the foreach method executes the provided callback once for each key of the map which actually exist.
... each value is visited once, except in the case when it was deleted and re-added before foreach has finished.
... foreach executes the callback function once for each element in the map object.

Set.prototype.forEach() - JavaScript
the foreach() method executes a provided function once for each value in the set object, in insertion order.
... description the foreach() method executes the provided callback once for each value which actually exists in the set object.
... each value is visited once, except in the case when it was deleted and re-added before foreach() has finished.
... foreach() executes the callback function once for each element in the set object; it does not return a value.

Web audio codec guide - Web media technologies
for web developers, an even bigger concern is the network bandwidth needed in order to transfer audio, whether for streaming or to download it for use during gameplay.
... for information about the fundamental concepts behind how digital audio works, see the article digital audio concepts.
... for more information about these and other features of audio data, see audio data format and structure in digital audio concepts.
... the patents behind mp3 have expired, removing many or most licensing concerns around using mp3 files in your projects.

Image file type and format guide - Web media technologies
conceptually similar to the animated gif format which has been in use for decades, apng is more capable in that it supports a variety of color depths, whereas animated gif supports only 8-bit indexed color.
...internet explorer, which introduced png support in versions 4–5, did not fully support it until ie 9, and had many infamous bugs for many of the intervening years, including in the once-omnipresent internet explorer 6.
... xbm (x window system bitmap file) xbm (x bitmap) files were the first to be supported on the web, but are no longer used and should be avoided, as their format has potential security concerns.
... best choice fallback lossless webp or png; jpeg if compression artifacts aren't a concern png or jpeg; gif for screenshots with low color counts diagrams, drawings, and charts for any image that can be represented using vector graphics, svg is the best choice.

Codecs used by WebRTC - Web media technologies
customizing the codec list once you have a list of the available codecs, you can alter it and then send the revised list to rtcrtptransceiver.setcodecpreferences() to rearrange the codec list.
... that's done for each transceiver on the rtcpeerconnection; once all of the transceivers have been updated, we call the onnegotiationneeded event handler, which will create a new offer, update the local description, send the offer along to the remote peer, and so on, thereby triggering the renegotiation of the connection.
...once the list has been split up, they're concatenated back together with the entries matching the given mimetype first, followed by all of the other codecs.
... licensing terms before choosing a video codec, make sure you're aware of any licensing requirements around the codec you select; you can find information about possible licensing concerns in our main guide to video codecs used on the web.

Critical rendering path - Web Performance
once layout is determined, pixels are painted to the screen.
...once complete, the page is rendered, or 'painted' on the screen.
... layout once the render tree is built, layout becomes possible.
...once the render tree is created and layout occurs, the pixels can be painted to the screen.

Index - XSLT: Extensible Stylesheet Language Transformations
the javascript loads the .xsl file only on the first sort and sets the xslloaded variable to true once it has finished loading the file.
...once instantiated, an xsltprocessor has an xsltprocessor.importstylesheet() method that takes as an argument the xslt stylesheet to be used in the transformation.
... 14 an overview needshelp, needsmarkupwork, transforming_xml_with_xslt, xml, xslt the extensible stylesheet language/transform is a very powerful language, and a complete discussion of it is well beyond the scope of this article, but a brief discussion of some basic concepts will be helpful in understanding the description of netscape's capabilities that follows.
...because xslt permits no side-effects, once the value of the variable has been established, it remains the same until the variable goes out of scope 53 <xsl:when> element, reference, xslt, when the <xsl:when> element always appears within an <xsl:choose> element, acting like a case statement.

Using the WebAssembly JavaScript API - WebAssembly
note: if you are unfamiliar with the basic concepts mentioned in this article and need more explanation, read webassembly concepts first, then come back.
... in this memory model, any load or store can access any byte in the entire linear memory, which is necessary to faithfully represent c/c++ concepts like pointers.
... multiplicity now we’ve demonstrated usage of the main key webassembly building blocks, this is a good place to mention the concept of multiplicity.
...we also touched on the concept of multiplicity.

port - Archive of obsolete content
in a content script, to listen for "mymessage" sent from the main add-on code: // content-script.js self.port.on("mymessage", function handlemymessage(mymessagepayload) { // handle the message }); in the main add-on code, to listen for "mymessage" sent from a a content script: // main.js worker.port.on("mymessage", function handlemymessage(mymessagepayload) { // handle the message }); once() often you'll want to receive a message just once, then stop listening.
... the port object offers a shortcut to do this: the once() method.
... this example rewrites the content script in the port.removelistener() example so that it uses once(): // content-script.js function getfirstparagraph() { var paras = document.getelementsbytagname('p'); console.log(paras[0].textcontent); } self.port.once("get-first-para", getfirstparagraph); removelistener() you can use port.on() to listen for messages.

passwords - Archive of obsolete content
require("sdk/self").uri, oncomplete: function oncomplete(credentials) { credentials.foreach(function(credential) { console.log(credential.username); console.log(credential.password); }); } }); } parameters options : object required options: name type oncomplete function the callback function that is called once the function completes successfully.
... oncomplete function the callback function that is called once the function completes successfully.
... oncomplete function the callback function that is called once the function has completed successfully.

request - Archive of obsolete content
optionally the user may specify a collection of headers and content to send alongside the request and a callback which will be executed once the request completes.
... once a request object has been created a get request can be executed by calling its get() method, a post request by calling its post() method, and so on.
... each request object is designed to be used once.

widget - Archive of obsolete content
this may take one of the following values: "start": load content scripts immediately after the document element for the widget is inserted into the dom, but before the dom content itself has been loaded "ready": load content scripts once dom content has been loaded, corresponding to the domcontentloaded event "end": load content scripts once all the content (dom, js, css, images) for the widget has been loaded, at the time the window.onload event fires this property is optional and defaults to "end".
...this may have one of the following values: "start": load content scripts immediately after the document element for the widget is inserted into the dom, but before the dom content itself has been loaded "ready": load content scripts once dom content has been loaded, corresponding to the domcontentloaded event "end": load content scripts once all the content (dom, js, css, images) for the widget has been loaded, at the time the window.onload event fires contentscriptoptions read-only value exposed to content scripts under self.options property.
...this may have one of the following values: "start": load content scripts immediately after the document element for the widget view is inserted into the dom, but before the dom content itself has been loaded "ready": load content scripts once dom content has been loaded, corresponding to the domcontentloaded event "end": load content scripts once all the content (dom, js, css, images) for the widget view has been loaded, at the time the window.onload event fires contentscriptoptions read-only value exposed to content scripts under self.options property.

core/promise - Archive of obsolete content
this is the common case, but every once in a while, you will need to create a promise from scratch.
...note: a promise can be rejected or resolved only once.
...alue after a given time ms -- kind of promise based alternative to settimeout: function delay(ms, value) { let { promise, resolve } = defer(); settimeout(resolve, ms, value); return promise; } delay(10, 'hello world').then(console.log); // after 10ms => 'helo world' advanced usage if general defer and promised should be enough to doing almost anything you may think of with promises, but once you start using promises extensively you may discover some missing pieces and this section of documentation may help you to discover them.

event/core - Archive of obsolete content
an event listener may be registered to any event target using the on function: var { on, once, off, emit } = require('sdk/event/core'); var target = { name: 'target' }; on(target, 'message', function listener(event) { console.log('hello ' + event); }); on(target, 'data', console.log); an event of a specific type may be emitted on any event target object using the emit function.
...to avoid hassles of removing such listeners there is a convenient once function: once(target, 'load', function() { console.log('ready'); }); emit(target, 'load') // info: 'ready' emit(target, 'load') there are also convenient ways to remove registered listeners.
... once(target, type, listener) registers an event listener that is called only once: the next time an event of the specified type is emitted on the given event target.

ui/toolbar - Archive of obsolete content
once(event, listener) assign a listener to the first occurrence only of an event emitted by the toolbar.
... var { toolbar } = require("sdk/ui/toolbar"); var { frame } = require("sdk/ui/frame"); var frame = new frame({ url: "./frame.html" }); var toolbar = toolbar({ title: "my toolbar", items: [frame] }); toolbar.once("show", showing); toolbar.once("hide", hiding); function showing(e) { console.log("showing: " + e.title); } function hiding(e) { console.log("hiding: " + e.title); } parameters event : string the name of the event to listen to.
...for example, this code is equivalent to once(): var { toolbar } = require("sdk/ui/toolbar"); var { frame } = require("sdk/ui/frame"); var frame = new frame({ url: "./frame.html" }); var toolbar = toolbar({ title: "my toolbar", items: [frame] }); toolbar.on("show", showing); toolbar.on("hide", hiding); function showing(e) { console.log("showing: " + e.title); toolbar.removelistener("show", showing); } function hiding(e) { console.log("hiding: " + e.title); toolbar.removelistener("hide", hiding); } parameters event : string the event ...

Chapter 6: Firefox extensions and XUL applications - Archive of obsolete content
once you’ve finished your inspection, you can continue and let the halted program resume execution.
... use step over to avoid a function, and step into to always call it; once you are done investigating a function, use step out, and then you can step into the next function.
... the next command will import the source code: gonzui-import.exe mozilla once the import process is complete, type the following command to launch the gonzui server: gonzui-server.exe now you can access gonzui from your web browser by typing the following into your location bar : http://localhost:46984 this lets you browse all packages, click on links to traverse them, and take traversed-link locations as search starting points (figure a).

Chapter 4: Using XPCOM—Implementing advanced processes - Archive of obsolete content
manipulating files using xpcom xpcom provides a number of interfaces allowing you to perform file manipulations without concern for whether you are running on windows, mac os x, or linux.
...once the process is complete, you should close all streams.
...here again, once the process is complete, you should close all streams.

Introduction - Archive of obsolete content
we'll start with a brief introduction to some key concepts, in case you're not familiar with mozilla and firefox.
... mozilla and firefox the term mozilla can be used to refer to several concepts: the mozilla project, the mozilla foundation, the mozilla corporation and the old mozilla browser.
... on to the tutorial with the basic concepts out of the way, we can now get right into extension development.

Drag and Drop JavaScript Wrapper - Archive of obsolete content
once called, it starts a drag for the string data "cabbage".
...once you have the data, you can add it to the element is some way.
...var textobserver = { ondrop : function (event, transferdata, session) { event.target.setattribute("value",transferdata.data); } } the flavour system used allows multiple objects of various types to be dragged at once and also allows alternative forms of the data to be dragged.

Migrate apps from Internet Explorer to Mozilla - Archive of obsolete content
browsers, like internet explorer 4, that were built before the conception of w3c standards inherited many quirks.
...once turned into the editor, commands can run on the document through the execcommand command.
...if the call is asynchronous, then give the onload member a function reference, which is called once the request has completed.

Merging TraceMonkey Repo - Archive of obsolete content
inspecting the files at those two changesets can be helpful: hg cat -c changeset filename once all the conflict markers are removed, you've performed the manual resolution, which you tell to mercurial by running hg resolve -m filename.
...once you've resolved all the files, all the entries in hg resolve -l will have rs next to them.
... once you've pushed to mozilla-central, do a bugzilla search for bugs that are not marked as resolved but have fixed-in-tracemonkey in the whiteboard.

URIs and URLs - Archive of obsolete content
the resource is the conceptual mapping to an entity or set of entities, not necessarily the entity which corresponds to that mapping at any particular instance in time.
... thus, a resource can remain constant even when its content---the entities to which it currently corresponds---changes over time, provided that the conceptual mapping is not changed in the process.
...also a string should not be escaped more than once.

Anonymous Content - Archive of obsolete content
anonymous content introduces the concept of scope to nodes within a document.
...as far as the bound element is concerned, it retains focus throughout the two events.
... as far as css is concerned, anonymous content nodes are children (or descendants) of the bound element, they are ancestors of explicit content, and they are siblings of the explicit content.

Creating XPI Installer Modules - Archive of obsolete content
once you have created a package like the one described here, mozilla users can download and install it in a single step.
...the chrome:// url pointer corresponds to the directory mozilla/bin/chrome/barley/content, where the main xul file and the other resources live once they are installed.
...using a zip archiver[zip], create a new archive of the content/ subdirectory and name it barley.jar: once this step is complete, the barley package is in the same state as the jar packages of the mozilla ui.

Learn XPI Installer Scripting by Example - Archive of obsolete content
adding files and directories (full of files) to the install once you have verified that the target can accomodate the software to be installed and initialized the actual installation, you must add files and directories to the installation in order to have them installed.
... executing the installation once you have added all the files to the installation, the final step is to actually execute the installation.
... code used to execute the installation appears in theinstall.js file as follows: if (err==success) { err = performinstall(); logcomment("performinstall() returned: " + err); } else { cancelinstall(err); logcomment("cancelinstall() due to error: " + err); } } else cancelinstall(insufficient_disk_space); performinstall is the function used to execute the install once it has been initialized and loaded, and it is the last step to installing the software.

Building Menus With Templates - Archive of obsolete content
however, unlike with other elements, the content of a menu is only generated once the menu has been opened.
...this causes the menupopup to only be created once.
...again, the popup is only created once since the uri attribute is on the menuitem element.

Focus and Selection - Archive of obsolete content
once the label in the example is focused, it can respond to key presses.
...however it only fires once the textbox loses the focus, thus, only once per set of changes.
...once you have the start and end positions, you can pull out the substring from the whole text.

XUL accessibility guidelines - Archive of obsolete content
in addition, there is an active community of accessibility developers within the mozilla project that will be happy to help you with any concerns or questions you have in regards to making your xul applications fully accessible.
...the problem occurs when a developer decides to add functionality that jumps the user to the second form field once 3 digits have been entered into the first form field.
...usually captioning and transcribing go hand in hand, once you have one its easy to produce the other.

The Implementation of the Application Object Model - Archive of obsolete content
we're still cross-platform, since we'd only have to write widgets like trees and toolbars once!
...the answer itself implied a concession that some newly-architected system that connected directly into the dom apis would be preferable to rdf if only there were time to engineer it.
...give an example once i actually know what the naming scheme will be.

Creating XULRunner Apps with the Mozilla Build System - Archive of obsolete content
building with a prebuilt sdk once you've downloaded the xulrunner sdk, you'll need a .mozconfig of your own.
...in this case you can basically copy over the file as is, since once again variables are used for things like the application name and version.
...it's got a lot of stuff in it, but once again you can mostly ignore this and copy the whole directory over from mccoy.

Introduction to SSL - Archive of obsolete content
the document assumes that you are familiar with the basic concepts of public-key cryptography, as summarized in "introduction to public-key cryptography." the ssl protocol the transmission control protocol/internet protocol (tcp/ip) governs the transport and routing of data over the internet.
... these capabilities address fundamental concerns about communication over the internet and other tcp/ip networks: ssl server authentication allows a user to confirm a server's identity.
... however, since 40-bit ciphers can be broken relatively quickly, administrators whose user communities can use stronger ciphers without violating export restrictions should disable the 40-bit ciphers if they are concerned about access to data by eavesdroppers.

Browser Detection and Cross Browser Support - Archive of obsolete content
once that happens, the only place your web site will be found is on the web archive.
...for example, it is conceivable that someday there will exist branch tags similar to 2.2.0 and 2.12.36.
...if you are concerned about a specific security issue in gecko and know for example that all gecko browsers contain a fix for the issue after a certain date, you can check that the navigator.productsub value is after that date.

The Business Benefits of Web Standards - Archive of obsolete content
the style sheet only needs to load once and then it is cached.
...in the same way that standards hugely reduce the concern we need to have for browser differences, they also reduce the differences between the way search engines rank pages.
...conversely once the content is to hand the development/publishing process should be lighteningly fast.

GLSL Shaders - Game development
vertex shaders vertex shaders manipulate coordinates in a 3d space and are called once per vertex.
... fragment shaders fragment (or texture) shaders define rgba (red, blue, green, alpha) colors for each pixel being processed — a single fragment shader is called once per pixel.
...be sure to read three.js tutorial first to grasp the concept of the scene, its objects, and materials.

3D games on the Web - Game development
advanced concepts you can do a lot more with webgl.
... there are some advanced concepts which you should dive into and learn more about — like shaders, collision detection, or the latest hot topic: virtual reality on the web.
...we have information available for you to learn from: 2d collision detection 3d collision detection webxr the concept of virtual reality is not new, but it's storming onto the web thanks to hardware advancements such as the oculus rift, and the (currently experimental) webxr api for capturing information from vr and ar hardware and making it available for use in javascript applications.

Handling different text directions - Learn web development
once you start to look at css layout, and in particular the newer layout methods, this idea of block and inline becomes very important.
...however, ultimately we expect that people will transition to the logical versions for most things, as they make a lot of sense once you start also dealing with layout methods such as flexbox and grid.
... summary the concepts explained in this lesson are becoming increasingly important in css.

Floats - Learn web development
in this article we'll just concentrate on the proper uses of floats.
...s parturient montes, nascetur ridiculus mus.</p> body { width: 90%; max-width: 900px; margin: 0 auto; font: .9em/1.2 arial, helvetica, sans-serif } .wrapper { background-color: rgb(79,185,227); padding: 10px; color: #fff; } .box { float: left; margin: 15px; width: 150px; height: 150px; border-radius: 5px; background-color: rgb(207,232,220); padding: 1em; } once again, this is because the float has been taken out of normal flow.
...once again, the box should clear.

Grids - Learn web development
prerequisites: html basics (study introduction to html), and an idea of how css works (study introduction to css and styling boxes.) objective: to understand the fundamental concepts behind grid layout systems, and how to implement a grid layout using css grid.
... gaps between tracks to create gaps between tracks we use the properties grid-column-gap for gaps between columns, grid-row-gap for gaps between rows, and grid-gap to set both at once.
...you can also use the shorthand properties: grid-column grid-row these let you specify the start and end lines at once, separated by a / — a forward slash character.

Legacy layout methods - Learn web development
prerequisites: html basics (study introduction to html), and an idea of how css works (study introduction to css and styling boxes.) objective: to understand the fundamental concepts behind the grid layout systems used prior to css grid layout being available in browsers.
...cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus.</p> </div> each one of the columns needs an outer element to contain its content and let us manipulate all of it at once.
...working through the process of creating a grid with floats shows you how this works and also introduces some more advanced concepts to build on the things you learned in the lesson on floats and clearing.

Practical positioning examples - Learn web development
our simple example will look like this once we are finished: note: you can see the finished example running live at info-box.html (source code).
... note: some web developers take things even further, only having one page of information loaded at once, and dynamically changing the information shown using a javascript feature such as xmlhttprequest.
...this will work in ie9 and above (the smooth transition will work in ie10 and above.) this effect does have some concerns — this is a bit of an abuse of form elements, as they weren't intended for this purpose.

Responsive design - Learn web development
as more diverse screen sizes became available, the concept of responsive web design (rwd) appeared, a set of practices that allows web pages to alter their layout and appearance to suit different screen widths, resolutions, etc.
... prerequisites: html basics (study introduction to html), and an idea of how css works (study css first steps and css building blocks.) objective: to understand the fundamental concepts and history of responsive design.
...essentially, the vw unit adds on top of that zoomed value: h1 { font-size: calc(1.5rem + 3vw); } this means that we only need to specify the font size for the heading once, rather than set it up for mobile and redefine it in the media queries.

Supporting older browsers - Learn web development
once you know the browsers that come to your site, you can assess any technology that you want to use against how well it is supported and how easily you can provide an alternative for visitors who do not have that technology available.
...gb(79,185,227); padding: 10px; max-width: 400px; display: grid; grid-template-columns: 1fr 1fr 1fr; } .item { float: left; border-radius: 5px; background-color: rgb(207,232,220); padding: 1em; } <div class="wrapper"> <div class="item">item one</div> <div class="item">item two</div> <div class="item">item three</div> </div> note: the clear property also has no effect once the cleared item becomes a grid item, so you could have a layout with a cleared footer, which is then turned into a grid layout.
...in grid however that 33.333% is calculated from the grid area the item is placed in, so it actually becomes a third of the size we want once the grid layout is introduced.

Common questions - Learn web development
in this article we describe various web-related concepts: webpages, websites, web servers, and search engines.
... with hypertext and http, url is a key concept when it comes to the internet.
... this article introduces the basic concepts behind web accessibility.

Basic native form controls - Learn web development
this is used to create a form control that is invisible to the user, but is still sent to the server along with the rest of the form data once submitted — for example you might want to submit a timestamp to the server stating when an order was placed.
...for most form widgets, once the form is submitted all widgets that have a name attribute are sent, even if no value has been filled out.
...once one of the radio buttons in a same-named group of buttons is checked, it is not possible for the user to uncheck all of the buttons without resetting the form.

How to build custom form controls - Learn web development
once we know how to change states, it is important to define how to change the control's value: the value changes when: the user clicks on an option when the control is in the open state.
...on the other hand, if you consider that the active state and the open state overlap a bit, the value may change but the option will definitely not be highlighted accordingly, once again because we did not define any keyboard interactions over options when the control is in its opened state (we have only defined what should happen when the control is opened, but nothing after that).
...for any interaction you do add, it is vital to spend time in the design stage; if you define a behavior poorly, or forget to define one, it will be very hard to redefine it once the users have gotten used to it.

UI pseudo-classes - Learn web development
note: a number of the pseudo-classes discussed here are concerned with styling form controls based on their validation state (is their data valid, or not?) you'll learn much more about setting and controlling validation constraints in our next article — client-side form validation — but for now we'll keep things simple with regards to form validation, so it doesn't confuse things.
... styling inputs based on whether they are required or not one of the most basic concepts with regards to client-side form validation is whether a form input is required (it has to be filled in before the form can be submitted) or optional.
... styling controls based on whether their data is valid the other really important, fundamental concept in form validation is whether a form control's data is valid or not (in the case of numerical data, we can also talk about in-range and out-of-range data).

Asynchronous JavaScript - Learn web development
if you are not familiar with the concept of asynchronous programming, you should definitely start with the general asynchronous programming concepts article in this module.
... guides general asynchronous programming concepts in this article we'll run through a number of important concepts relating to asynchronous programming, and how this looks in web browsers and javascript.
... you should understand these concepts before working through the other articles in the module.

Build your own function - Learn web development
when you save your code and reload it in the browser, you'll see the little message box appear immediately, only once.
... we are only calling it once, after all.
...in the next article we'll wrap up functions by explaining another essential related concept — return values.

Fetching data from the server - Learn web development
this seemingly small detail has had a huge impact on the performance and behavior of sites, so in this article, we'll explain the concept and look at technologies that make it possible, such as xmlhttprequest and the fetch api.
...here, however, we want to keep it simple and concentrate on the client-side part of this.
... once we've successfully received our blob, we create an object url out of it using createobjecturl().

Componentizing our React app - Learn web development
once you're confident that your component is getting its props, you can replace every occurrence of eat with your name prop.
...once again, we want to reuse most of the ui that makes up a <todo /> component, but change one thing.
...once you’re done, the todo component's <input /> element will read like this: <input id="todo-0" type="checkbox" defaultchecked={props.completed} /> and your browser should update to show only eat being checked: if you change each <todo /> component’s completed prop, your browser will check or uncheck the equivalent rendered checkboxes accordingly.

React interactivity: Events and state - Learn web development
once we have our callback prop, we can call it inside <form /> to send the right data to <app />.
... this is a lot to take in at once, so let's try it out.
... <input type="text" id="new-todo-input" classname="input input__lg" name="text" autocomplete="off" value={name} /> change "use hooks!" to an empty string once you're done; this is what we want for our initial state.

Starting our Svelte Todo list app - Learn web development
this will be the basic functionality that we'll be developing in this tutorial series, plus we'll look at some more advanced concepts along the way too.
... repl to code along with us using the repl, start at https://svelte.dev/repl/b7b831ea3a354d3789cefbc31e2ca495?version=3.23.2 todo list app features this is how our todo list app wil look like once it's ready: using this ui our user will be able to: browse their tasks.
...once we have put our styles in place, though, any element with this class will be hidden from sighted users and still available to screen reader users — this is because these words are not needed by sighted users; they are there to provide more information about what the button does for screenreader users that do not have the extra visual context to help them.

Advanced Svelte: Reactivity, lifecycle, accessibility - Learn web development
code along with us git clone the github repo (if you haven't already done it) with: git clone https://github.com/opensas/mdn-svelte-tutorial.git then to get to the current app state, run cd mdn-svelte-tutorial/05-advanced-concepts or directly download the folder's content: npx degit opensas/mdn-svelte-tutorial/05-advanced-concepts remember to run npm install && npm run dev to start your app in development mode.
...now you should be able to check and uncheck all your todos at once.
... don't forget to pass the prop into moreactions from inside todos.svelte, where the component is called: <moreactions {todos} on:checkall={e => checkalltodos(e.detail)} on:removecompleted={removecompletedtodos} /> working with the dom: focusing on the details now that we have completed all of the app's required functionality, we'll concentrate on some accessibility features that will improve the usability of our app for both keyboard-only and screenreader users.

Dynamic behavior in Svelte: working with variables and props - Learn web development
objective: learn and put into practice some basic svelte concepts, like creating components, passing data using props, render javascript expressions into our markup, modify the components state and iterating over lists.
...once you get used to it, there's no going back.
...once.

Getting started with Vue - Learn web development
to install the cli, run the following command in your terminal: npm install --global @vue/cli or if you'd prefer to use yarn: yarn global add @vue/cli once installed, to initialize a new project you can then open a terminal in the directory you want to create the project in, and run vue create <project-name>.
...once they are selected, press enter to proceed.
... in the next article we'll build our first custom component, and look at some important concepts such as passing props into it and saving its data state.

Strategies for carrying out testing - Learn web development
objective: to gain an understanding of the high-level concepts involved in cross-browser testing.
... note: you can only have one version of ie or edge installed on a machine at once, so you will probably have to use virtual machine, or other strategy to do the testing you need.
... once you've finished filling in everything, press the get tracking id button, then accept the terms of service that appear.

Chrome Worker Modules
you only need to do it once for each worker, from within the chrome worker itself: importscripts("resource://gre/modules/workers/require.js"); note: although you only need to do this once for each worker, it doesn't hurt if you do it more than once.
...d it to either global value exports, as follows: /* file mymodule.js */ let secretkey = "this is a secret"; let publickey = "this is public"; exports.key = publickey; // secretkey is not exported // publickey is exported with name "key" alternatively, if you prefer that style, you may write // variable |module| is a special global introduced by require() module.exports = { key: publickey }; once this is done, we may load the module and use the values that have been exported // assuming that mymodule.js is installed to resource://gre/modules/mymodule.js let module = require("resource://gre/modules/mymodule.js") foo(module.key); // module.key == "this is public"; // however, secretkey is not exported and cannot be used for the installation of resources, please see the documentation on...
...you should not modify exports or module.exports once your module initialization is complete.

Gecko info for Windows accessibility vendors
once you know that you have a document, go up the ancestor chain of windows until you see a mozillacontentwindowclass or a mozillauiwindowclass.
... iaccessibles persist unless the document changes, retrieving the iaccessible more than once for the same object will return the same iaccessible*.
... once the new page is ready to be displayed and traversed via its iaccessible tree, the old content window is destroyed, and a new window is created.

A bird's-eye view of the Mozilla framework
thehelp viewer files referenced in the article are located in /seamonkey/extensions/help/ this article also assumes you are familiar with the javascript and c++ programming languages, object-oriented programming (oop) terminology and design concepts, the microsoft® component object model (com), and the corba omg interface definition language (idl).
... organization this article first covers some conceptual groundwork, then walks through a user scenario to illustrate how key mozilla architectural components work together to support a simplehelp viewer ui action.
...once loaded, a module or package has full access to the xpcom objects of all the other modules in the runtime environment.

The Firefox codebase: CSS Guidelines
once the two things above have been checked, check if the other rule you are overriding contains !important, if that is case, try putting it in question, because it might have become obsolete.
... finally, once you have checked all the things above, you can permit yourself to use !important along with a comment why it is needed.
...generally, when specifying -moz-appearance: foo; you're giving hints as to how something should act, however -moz-appearance: none; is probably saying 'ignore browser preconceptions - i want a blank sheet', so that's more visual.

Contributing to the Mozilla code base
once you have found something to work on, go ahead and comment!
...ozilla.org or #developers:mozilla.org check out https://developer.mozilla.org/docs/developer_guide and its parent document, https://developer.mozilla.org/docs/mozilla our reviewer checklist is very useful, if you have a patch near completion, and seek a favorable review utilize our build tool mach, its linting, static analysis, and other code checking features step 3: get your code reviewed once you fix the bug, you can advance to having your code reviewed.
... step 4b: follow it up once you've asked for a review, a reviewer will often respond within a day or two, reviewing the patch, or saying when they will be able to review it, perhaps due to a backlog.

SVG Guidelines
once again, "it depends".
...nd use class names or svg attributes examples here are some examples for excessive number precision: 5.000000e-02 → 0.05 (as seen here) -3.728928e-10 → 0 (as seen here) translate(0.000000, -1.000000) → translate(0, -1) (as seen here) as for descriptive ids: for gradients: svg_id1 → gradient1 (as seen here) use of class names avoid using a class if that class is only used once in the file if that class only sets a fill or a stroke, it's better to set the fill/stroke directly on the actual shape, instead of introducing a class just for that shape.
... avoid using a <use> tag when that <use> tag is being referenced only once in the whole file.

Displaying Places information using views
once notified, the view is responsible for updating itself.
...don't break the separation of concerns here.
...if your custom view is used only once in your application, code similar to the above will likely be sufficient; it's enough to create a single placestreeview object, modify it, and attach it to a regular tree.

Message manager overview
process scripts are most likely to be useful when an extension wants to run some code only once in the content process, to access some global service: for example, to register an observer or a content policy.
...multiprocess firefox has the concept of: a "parent process" "child processes" which are processes spawned by the parent process.
...this is the recommended way to load a script that executes just once per child process, which is something you might want to do if you are interacting with some global service (for example, adding listeners to observer notifications or registering a content policy).

Process scripts
but if you register it in a frame script, and the frame script is loaded more than once, you'll register the content policy more than once, which probably isn't what you intend.
... similarly, some observer notifications must be registered in the content process, but if you do this in a frame script, and the frame script is loaded more than once, then you will get multiple notifications for that event.
...to send messages to the chrome side: // process-script.js if (services.appinfo.processtype == services.appinfo.process_type_content) { dump("welcome to the process script in a content process"); } else { dump("welcome to the process script in the main process"); } // message is sent using contentprocessmessagemanager sendasyncmessage("hello"); in this example, the dump() statement will run once in each content process as well as in the main process.

HTML parser threading
once a unicode decoder has been set up, dodataavailable passes the byte data to the decoder whose output is accumulated into a linked list of nshtml5owningutf16buffer objects.
...it's more efficient to obtain a mutex only every once in a while when a whole bunch of tree ops is moved to or from the staging queue.
...(again, here we get to move a bunch of tree ops by obtaining a mutex once instead of having to synchronize thread on a per-tree op basis.) if the executor isn't reading from a stage, it calls nshtml5parser::parseuntilblocked() to parse potential document.write()-generated data into tree ops.

Extending a Protocol
once it's compiled, ./mach run and you should be able to spin up the developer console and type: navigator.echo("hi!"); that will return a pending promise that never settles.
...ady_addrefed<echoparent> windowglobalparent::allocpechoparent() { puts("windowglobalparent::allocpechoparent was called"); refptr<echoparent> actor = new echoparent(); return actor.forget(); } bool windowglobalparent::deallocpechoparent( pechoparent* aactor) { refptr actor = dont_addref(static_cast(aactor)); return true; } the "puts()" there will help us see what's going on once we get things going.
... naturally, we want to remove that once we done implementing.

JavaScript-DOM Prototypes in Mozilla
once the registration is done, the nsdomclassinfo code uses the registry every time a named property is resolved on a global object (because of this, the nsscriptnamespacemanager needs to be pretty fast at looking things up in its registry; that's why it is a hash table).
...once the name of the parent interface is known (and the name is not nsisupports) the code will look up a property by that name on the global object.
...this is also done only once per class, nsdomclassinfo::postcreate() checks if the prototype of the prototype of the wrapper jsobject (i.e.

Bootstrapping a new locale
untrusted connection in the example above), like so (example for polish): <!entity certerror.pagetitle "niezaufane połączenie"> once you have translated all the <!entity> strings in this file, you should save your work and open the next .dtd or .property file.
... once you have that account, send the l10n-drivers the details to be added as a "writer".
...set the general.useragent.locale to your language code, in this case, en-x-dude, and restart firefox once more.

Index
this is only necessary once.
... 7 l10n testing with xcode firefox for ios, localization once you have your l10n testing environment set up in xcode, testing your firefox on ios localization is a breeze.
...if you don't have a lot of experience with code, you might even be concerned that you've broken something (oops!).

Localizing with Koala
on the other hand, "manage search engines..." is generated only once, on start-up, and doesn't need to change.
... once you translated the searchendcap.label entity, add the other one from this file, i.e.
...once you "hg add" every new file in the repository that you want to track in mercurial, you will need to "hg commit" these new files so as to create a new revision in the repository's history.

Release phase
once you've made sure the outgoing output is accurate, push this changeset to hg.mozilla.org by running the hg push command.
...once attached, open the attachment details.
...once again, congratulations!

Activity Monitor, Battery Status Menu and top
when you open this menu for the first time in a while it says “collecting power usage information” for a few seconds, and if you have top open during that time you'll see that, once again, systemstats is running and using a lot of cpu.
... testing shows that once an energy-intensive application is started it takes less than a minute for it to show up in the battery status menu.
... and once the application stops using high amounts of energy it takes a few minutes to disappear.

Investigating leaks using DMD heap scan mode
once it has started, go through the steps you need to reproduce your leak.
...conveniently, you can usually do both at once using the cycle collector log.
... both kinds of preprocessing are done by the dmd.py script, which can be invoked like this: $objdir/dist/bin/dmd.py --clamp-contents dmd-$pid.log.gz this can take a few minutes due to symbolification, but you only need to run it once on a log file.

Reporting a Performance Problem
there will be a button in the top right labeled 'publish' which will allow you to upload this profile and once completed will write out a link.
... once uploaded, copy permalink url to your clipboard by right clicking and add the profile url to a bug for your performance problem and/or send it to the appropriate person.
... your first reflex once you find what addon is slowing down the profile might be to disable it and search for alternatives.

McCoy
once you have a password set you can change it from the keys menu and you will have to enter it each time you run mccoy.
... once you have a key you need to add its public part to your add-on's install.rdf file.
... releasing an update once you are ready to release an updated version of your add-on you must create yourself an update.rdf file.

Process Initialization
pr_init pr_initialize pr_initialized pr_cleanup pr_disableclockinterrupts pr_blockclockinterrupts pr_unblockclockinterrupts pr_setconcurrency pr_processexit pr_abort module initialization initialization can be tricky in a threaded environment, especially initialization that must happen exactly once.
... pr_callonce ensures that such initialization code is called only once.
... prcalloncetype prcalloncefn pr_callonce ...

NSS API Guidelines
(frees are allowed.) the arena_destructor_list preprocessor definition, and the code it encloses, are an effort to make the following work together: arenas, letting you allocate stuff and then removing them all at once lazy creation of pure-memory objects from asn.1 blobs, for example use of nsspkixcertificate doesn't drag all the code in for all constituent objects, unless they're actually being used our agressive pointer-tracking facility all these are useful, but they don't combine well.
... error handling nss 3.0 introduces the concept of an error stack.
...once that data pointer is made visible to the 'outside', either by returning the pointer, or attaching the pointer to an existing visible data structure, access to the data should be protected.

PKCS11 FAQ
once you've installed the module, the module's certificates simply appear in the list of certificates displayed in the certificate window.
... once nss starts using a token for a given operation (like s/mime or ssl), it works hard to keep using that same token (so keys don't get moved around).
... at some later point, the ca presents the certificate to you (as part of this keygen, or in an e-mail, or you go back and fetch it from a web page once the ca notifies you of the arrival of the new certificate).

Hacking Tips
once the breakpoint is on codegenerator function of the lir instruction, add a command to generate a static breakpoint in the generated code.
...() (gdb) once you hit the generated breakpoint, you can replace it by a gdb breakpoint to make it conditional, the procedure is to first replace the generated breakpoint by a nop instruction, and to set a breakpoint at the address of the nop.
...in lldb, if the allocation failure number shown is 1500, run `continue -i 1498` (subtracted 2 because we've already hit it once and don't want to skip the last).

Property cache
so the lookup must happen only once.
...it walks the scope chain and prototype chain as described above only once, at compile time, and emits code containing the pointer to the object that contains the property.
... when a prototype gains a property that could invalidate an entry of this type, rt->protohazardshape is bumped, effectively marking all such entries invalid at once.

JSAPI Cookbook
*/ if (!js_definefunction(cx, global, "justforfun", &justforfun, 0, 0)) return false; to define many jsapi functions at once, use js_definefunctions.
... /* jsapi */ js::rootedvalue x(cx); if (!y.isobject()) return throwerror(cx, global, "parameter y must be an object.", __file__, __line__); /* see the #throw example */ js::rootedobject yobj(cx, &y.toobject()); if (!js_getproperty(cx, yobj, "myprop", &x)) return false; setting a property // javascript y.myprop = x; see "getting a property", above, concerning the case where y is not an object.
... /* jsapi */ assert(y.isobject()); js::rootedobject yobj(cx, &y.toobject()); if (!js_setproperty(cx, yobj, "myprop", &x)) return false; checking for a property // javascript if ("myprop" in y) { // then do something } see "getting a property", above, concerning the case where y is not an object.

JS_Init
once this method has succeeded, it is safe to call js_newruntime and other jsapi methods.
...once it has been used, it is safe to call any jsapi method, and it remains safe to do so until js_shutdown is correctly called.
... in the past js_init once had the signature jsruntime * js_init(uint32_t maxbytes) and was used to create new jsruntime instances.

SpiderMonkey 31
once this method has been successfully called, it's okay to call js_newruntime and all the other existing spidermonkey apis as usual.
... once all jsapi operation has completed, the corresponding js_shutdown method uninitializes spidermonkey, cleaning up memory and allocations performed by js_init.
...we have chosen to concentrate on performance and correctness as primary concerns instead.

Signing Mozilla apps for Mac OS X
once you have that you can do the following to create your id: open the developer certificate utility.
...once the application has been signed, the signature of an application bundle can be validated by calling: codesign -vvvv application.app where application.app is the application bundle you wish to validate.
...once the application bundle is signed, this file will contain the hashes/checksums of all files that are included in the signature.

Animated PNG graphics
conceptually, each frame is constructed in the output buffer before being composited onto the canvas.
... conceptually, at the beginning of each play the output buffer must be completely initialized to a fully transparent black rectangle, with width and height dimensions from the 'ihdr' chunk.
...conceptually, such scaling occurs while mapping the output buffer onto the canvas.

Gecko object attributes
exposed in aria: aria-relevant container-atomic is this change inside a region that should always be presented at once.
...a state change event for the a11y api's busy state will be fired on the container object currently marked as busy, once it is no longer busy.
...the entire atomic region should be presented once when it is finally no longer busy.

Embedded Dialog API
applications concerned with presenting a consistent dialog appearance have the option of implementing the complete dialog posing api.
...applications concerned with a consistent overall dialog appearance will probably choose to implement the complete api as well.
...advanced windowing api embedding applications concerned with ensuring that dialogs posed by gecko are consistent in appearance and behaviour with dialogs posed directly by the application itself face a choice.

Building the WebLock UI
the locking ui once you have the basic xul wrapper set up for your interface, the next step is to define that part of the interface that locks and unlocks the browser.
...and how do you access it once it's installed?
... once it's installed and registered, the weblock component itself is ready to go: xpcom finds it and adds it to the list of registered components, and then weblock observes the xpcom startup event and initializes itself.

Component Internals
once the manifest files are read in, xpcom checks to see if there are any components that need to be registered.
... once registration is complete and the notifications have fired, xpcom is ready to be used by the application.
... note also that xpcom services may deny you access once you have received the shutdown notification.

Mozilla internal string guide
once you are familiar with them, see the appendix describing what class to use when.
...once you are familiar with them, see the appendix describing what class to use when.
... once you are done writing, call finish().

Observer Notifications
user-interaction-active nsidomwindow null sent once every 5000ms while this chrome document sees some kind of user activity (for example, keyboard or mouse events), and at the exact moment of the state transition from idle to active.
... sent once a day while the user is idle.
...once this has been sent, no places features will work.

nsIContentPrefService2
callback handleresult is called once unless no such preference exists, in which case handleresult is not called at all.
... callback handleresult is called once for each preference.
... callback handleresult is called once unless no such preference exists, in which case handleresult is not called at all.

nsIDownload
download objects are used by the download manager (see nsidownloadmanager to manage files that are queued to download, being downloaded, and finished being downloaded.) inherits from: nsitransfer last changed in gecko 1.9.1 (firefox 3.5 / thunderbird 3.0 / seamonkey 2.0) note: once the download is completed, the download manager stops updating the nsidownload object.
...once the download is complete, this value is set to null.
... mimeinfo nsimimeinfo provides the targets relevant mime information, including its mime type, helper application, and whether or not the helper should be executed automatically once the download is complete.

nsIMIMEInputStream
not allowed to be changed once the stream has been started to be read.
...may not be called once the stream has been started to be read.
...may not be called once the stream has been started to be read.

nsINavHistoryResultViewObserver
void ondrop(in long row, in long orientation); void ontoggleopenstate(in long index); void oncycleheader(in nsitreecolumn column); void oncyclecell(in long row, in nsitreecolumn column); void onselectionchanged(); void onperformaction(in wstring action); void onperformactiononrow(in wstring action, in long row); void onperformactiononcell(in wstring action, in long row, in nsitreecolumn column); constants constant value description drop_before -1 the drag operation wishes to insert the dragged item before the indicated row.
... onperformactiononcell() this method provides a command api that can be used to invoke commands on a specified cell.
... void onperformactiononcell( in wstring action, in long row, in nsitreecolumn column ); parameters action a string identifying the action to be performed.

nsITreeView
iner(in long index); boolean iscontainerempty(in long index); boolean iscontaineropen(in long index); boolean iseditable(in long row, in nsitreecolumn col); boolean isselectable(in long row, in nsitreecolumn col); boolean isseparator(in long index); boolean issorted(); void performaction(in wstring action); void performactiononcell(in wstring action, in long row, in nsitreecolumn col); void performactiononrow(in wstring action, in long row); void selectionchanged(); void setcelltext(in long row, in nsitreecolumn col, in astring value); void setcellvalue(in long row, in nsitreecolumn col, in astring value); void settree(in nsitreeboxobject tree); void toggleopenstate(i...
... performactiononcell() a command api that can be used to invoke commands on a specific cell.
... void performactiononcell( in wstring action, in long row, in nsitreecolumn col ); parameters action the action to perform.

nsIZipWriter
1.0 66 introduced gecko 1.9 inherits from: nsisupports last changed in gecko 1.9 (firefox 3) once all the operations you wish to perform are added to the queue, a call to processqueue() will perform the operations in the order they were added to the queue.
... aqueue true to place the remove operation into the queue, or false to process it at once.
...once you pick a folder, it will create a zip file inside this folder with the same name as the folder.

Reference Manual
several reasons: it would become inconvenient take the address of an nscomptr in all other situations; the name "getter_addrefs" enforces the notion that a certain behavior is required of the getter; and once upon a time, there was another possibility (as you're about to learn).
...once upon a time, there was, but it went away for three reasons: it is against the rules of xpcom for a getter to return a non-addrefed interface pointer through a parameter (if you see it, report a bug).
...performance concerns should not deter you from using nscomptr.

Virtualenv
using virtualenv once you have virtualenv installed, you can make virtual environments: > virtualenv tmp new python executable in tmp/bin/python installing setuptools............done.
...bin/activate once the virtualenv is activated, the virtualenv's python (and other executables) will be on your path and you will have a new environment variable, virtual_env, that points to the path of the virtualenv, as well as a deactivate function for deactivating the virtualenv.
... the mozilla build system mostly uses .pth files instead of the more typically used python setup.py develop or python setup.py install to install python modules in to the virtualenv's python path due to performance concerns (although such functionality is available via the setup.py keyword in a packages.txt file).

Streams - Plugins
once all data in the stream has been written to the plug-in, the stream is destroyed.
...once the plug-in returns from this method, the browser deletes the npstream object.
...if the plug-in allocates memory for the entire stream at once, it can return a large number.

Edit Shape Paths in CSS - Firefox Developer Tools
once you have selected your element, you should see the shape icon alongside any valid value, e.g.
... understanding the lines drawn by the editor once you have selected a shape on your page, the shape path editor will draw lines to help you understand the path that is being created.
...once again, clipping will occur if you exceed the bounds of the margin box.

AbstractRange - Web APIs
staticrange a staticrange is a basic range which cannot be changed once it's been created.
...this is useful when you need to specify a range that will only be used once, since it avoids the performance and resource impact of the more complex range interface.
...once it's been loaded, the page is a tree of dom node objects, so you need to specify the beginning and ending locations of a range in terms of nodes and positions within nodes.

Animation.finished - Web APIs
the animation.finished read-only property of the web animations api returns a promise which resolves once the animation has finished playing.
...the new promise will resolve once the new animation sequence has completed.
... syntax var animationspromise = animation.finished; value a promise object which will resolve once the animation has finished running.

Background Tasks API - Web APIs
concepts and usage the main thread of a web browser is centered around its event loop.
... statusrefreshscheduled is used to track whether or not we've already scheduled an update of the status display box for the upcoming frame, so that we only do it once per frame the shim to function even if idle callbacks aren't supported.
...it's configured to call a function called runtaskqueue(), which we'll look at shortly, and with a timeout of 1 second, so that it will be run at least once per second even if there isn't any actual idle time available.

BaseAudioContext.createConvolver() - Web APIs
the example below uses a short sample of a concert hall crowd, so the reverb effect applied is really deep and echoey.
... // grab audio track via xhr for convolver node var soundsource, concerthallbuffer; ajaxrequest = new xmlhttprequest(); ajaxrequest.open('get', 'concert-crowd.ogg', true); ajaxrequest.responsetype = 'arraybuffer'; ajaxrequest.onload = function() { var audiodata = ajaxrequest.response; audioctx.decodeaudiodata(audiodata, function(buffer) { concerthallbuffer = buffer; soundsource = audioctx.createbuffersource(); soundsource.buffer = concerthallbuffer; }, function(e){"error with decoding audio data" + e.err}); } ajaxrequest.send(); ...
... convolver.buffer = concerthallbuffer; specifications specification status comment web audio apithe definition of 'createconvolver()' in that specification.

Transformations - Web APIs
saving and restoring state before we look at the transformation methods, let's look at two other methods which are indispensable once you start generating ever more complex drawings.
...however once we call the first restore() statement, the top drawing state is removed from the stack, and settings are restored.
... when the second restore() statement is called, the original state (the one we set up before the first call to save) is restored and the last rectangle is once again drawn in black.

Document.cookie - Web APIs
when user privacy is a concern, it's important that any web app implementation invalidate cookie data after a certain timeout instead of relying on the browser to do it.
...how cookies</button> example #2: get a sample cookie named test2 document.cookie = "test1=hello"; document.cookie = "test2=world"; const cookievalue = document.cookie .split('; ') .find(row => row.startswith('test2')) .split('=')[1]; function alertcookievalue() { alert(cookievalue); } <button onclick="alertcookievalue()">show cookie value</button> example #3: do something only once in order to use the following code, please replace all occurrences of the word dosomethingonlyonce (the name of the cookie) with a custom name.
... function doonce() { if (!document.cookie.split('; ').find(row => row.startswith('dosomethingonlyonce'))) { alert("do something here!"); document.cookie = "dosomethingonlyonce=true; expires=fri, 31 dec 9999 23:59:59 gmt"; } } <button onclick="doonce()">only do something once</button> example #4: reset the previous cookie function resetonce() { document.cookie = "dosomethingonlyonce=; expires=thu, 01 jan 1970 00:00:00 gmt"; } <button onclick="resetonce()">reset only once cookie</button> example #5: check a cookie existence //es5 if (document.cookie.split(';').some(function(item) { return item.trim().indexof('reader=') == 0 })) { console.log('the cookie "reader" exists (es5)') } //es2016 if (document.cookie.split(';').some((item) => item.trim().startswith('rea...

EffectTiming.fill - Web APIs
for example, setting fill to "none" means the animation's effects are not applied to the element if the current time is outside the range of times during which the animation is running, while "forwards" ensures that once the animation's end time has been passed, the element will continue to be drawn in the state it was in at its last rendered frame.
... here we specify that the animation should take 2000 milliseconds (2 seconds) to complete, should only run once, and that the fill mode should be "none".
...then, when the animation finishes running, the box instantaneously leaps back to its original state and is upright once again.

Event.initEvent() - Web APIs
once dispatched, it doesn't do anything anymore.
...once set, the read-only property event.bubbles will give its value.
...once set, the read-only property event.cancelable will give its value.

Using files from web applications - Web APIs
set up the image's load event handler to release the object url since it's no longer needed once the image has been loaded.
...once we have that list, it's trivial to go through it and create a new fileupload instance for each.
...this causes the throbber to disappear once the upload is complete.

Introduction to the File and Directory Entries API - Web APIs
about this document this introduction discusses essential concepts and terminology in the file and directory entries api.
... it gives you the big picture and orients you to key concepts.
... big concepts before you start using the file and directory entries api, you need to understand a few concepts: the file and directory entries api is a virtual representation of a file system the file and directory entries api can use different storage types browsers impose storage quota the file and directory entries api has asynchronous and synchronous versions when using the asynchronous api, alw...

Fullscreen API - Web APIs
the fullscreen api adds methods to present a specific element (and its descendants) in full-screen mode, and to exit full-screen mode once it is no longer needed.
...returns a promise which is resolved once full-screen mode has been completely shut off.
...returns a promise which is resolved once full-screen mode has been activated.

The HTML DOM API - Web APIs
html dom concepts and usage in this article, we'll focus on the parts of the html dom that involve engaging with html elements.
... nodes don't have any concept of including the content that is actually displayed in the document.
...from node, the element inherits concepts surrounding the ability for the element to be contained by another element, and to contain other elements itself.

IndexedDB API - Web APIs
this is the main landing page for mdn's indexeddb coverage — here we provide links to the full api reference and usage guides, browser support details, and some explanation of key concepts.
... key concepts and usage indexeddb is a transactional database system, like an sql-based rdbms.
... read more about the concepts behind indexeddb.

LocalFileSystemSync - Web APIs
basic concepts you can request access to a sandboxed file system by requesting localfilesystemsync object from within a web worker.
... for more concepts, see the counterpart article for the asynchronous api.
...for more details, see the article on basic concepts.

Recording a media element - Web APIs
function wait(delayinms) { return new promise(resolve => settimeout(resolve, delayinms)); } the wait() function returns a new promise which resolves once the specified number of milliseconds have elapsed.
...once that resolves, the array data is returned by startrecording() to its caller.
...as mentioned before, startrecording() returns a promise whose resolution handler is called (receiving as input an array of blob objects containing the chunks of recorded media data) once recording has completed.

Capabilities, constraints, and settings - Web APIs
the twin concepts of constraints and capabilities let the browser and web site or app exchange information about what constrainable properties the browser's implementation supports and what values it supports for each one.
... once the script knows whether the property or properties it wishes to use are supported, it can then check the capabilities of the api and its implementation by examining the object returned by the track's getcapabilities() method; this object lists each supported constraint and the values or range of values which are supported.
... once that's done, applyconstraints() is called on the audio track (if there is one) to apply the new audio constraints.

Permissions API - Web APIs
concepts and usage historically different apis handle their own permissions inconsistently — for example the notifications api allows for explicit checking of permission status and requesting permission, whereas the geolocation api doesn't (which causes problems if the user denied the initial permission request).
... the permissions api provides the tools to allow developers to implement a better user experience as far as permissions are concerned.
... once you have this object you can then perform permission-related tasks, for example querying a permission using the permissions.query() method to return a promise that resolves with the permissionstatus for a specific api.

RTCPeerConnection.setLocalDescription() - Web APIs
the method takes a single parameter—the session description—and it returns a promise which is fulfilled once the description has been changed, asynchronously.
... return value a promise which is fulfilled once the value of rtcpeerconnection.localdescription is successfully changed or rejected if the change cannot be applied (for example, if the specified description is incompatible with one or both of the peers on the connection).
... successcallback a javascript function which accepts no input parameters to be be called once the description has been successfully set.

RTCPeerConnection - Web APIs
it provides methods to connect to a remote peer, maintain and monitor the connection, and close the connection once it's no longer needed.
...instead of using this obsolete method, you should instead use addtrack() once for each track you wish to send to the remote peer.addtrack()the rtcpeerconnection method addtrack() adds a new media track to the set of tracks which will be transmitted to the other peer.close() the rtcpeerconnection.close() method closes the current peer connection.createanswer() the createanswer() method on the rtcpeerconnection interface creates an sdp answer to an offer received from a re...
...<<< make this a link once i know where that will be documented "connected" every ice transport used by the connection is either in use (state "connected" or "completed") or is closed (state "closed"); in addition, at least one transport is either "connected" or "completed".

RTCRtpParameters - Web APIs
this parameter cannot be changed once initially set.
...this parameter cannot be changed once initially set.
...this parameter cannot be changed once initially set.

Using Service Workers - Web APIs
this returns a promise for a created cache; once resolved, we then call a function that calls addall() on the created cache, which for its parameter takes an array of origin-relative urls to all the resources you want to cache.
... cloning the response is necessary because request and response streams can only be read once.
... they are each read once.

URL API - Web APIs
the url standard also defines concepts such as domains, hosts, and ip addresses, and also attempts to describe in a standard way the legacy application/x-www-form-urlencoded mime type used to submit web forms' contents as a set of key/value pairs.
... url concepts and usage the majority of the url standard is taken up by the definition of a url and how it is structured and parsed.
...for instance, try https://url-api.glitch.me?from=mdn&excitement=high&likelihood=inconceivable.

Lighting in WebGL - Web APIs
once you drop out the concept of point sources and specular lighting, there are two pieces of information we'll need in order to implement our directional lighting: we need to associate a surface normal with each vertex.
...3(0.3, 0.3, 0.3); highp vec3 directionallightcolor = vec3(1, 1, 1); highp vec3 directionalvector = normalize(vec3(0.85, 0.8, 0.75)); highp vec4 transformednormal = unormalmatrix * vec4(avertexnormal, 1.0); highp float directional = max(dot(transformednormal.xyz, directionalvector), 0.0); vlighting = ambientlight + (directionallightcolor * directional); } `; once the position of the vertex is computed, and we pass the coordinates of the texel corresponding to the vertex to the fragment shader, we can work on computing the shading for the vertex.
... once the amount of directional lighting is computed, we can generate the lighting value by taking the ambient light and adding in the product of the directional light's color and the amount of directional lighting to provide.

WebGL best practices - Web APIs
(conceptually releasing the handle's ref-pointer to the object) only once the object is unused in the implementation is it actually freed.
... instead of: function compileonce(gl, shader) { if (shader.compiled) return; gl.compileshader(shader); shader.compiled = true; } for (const [vs, fs, prog] of programs) { compileonce(gl, vs); compileonce(gl, fs); gl.linkprogram(prog); if (!gl.getprogramparameter(prog, gl.link_status)) { console.error('link failed: ' + gl.getprograminfolog(prog)); console.error('vs info-log: ' + gl.getshaderinfolog(vs)); c...
...onsole.error('fs info-log: ' + gl.getshaderinfolog(fs)); } } consider: function compileonce(gl, shader) { if (shader.compiled) return; gl.compileshader(shader); shader.compiled = true; } for (const [vs, fs, prog] of programs) { compileonce(gl, vs); compileonce(gl, fs); } for (const [vs, fs, prog] of programs) { gl.linkprogram(prog); } for (const [vs, fs, prog] of programs) { if (!gl.getprogramparameter(prog, gl.link_status)) { console.error('link failed: ' + gl.getprograminfolog(prog)); console.error('vs info-log: ' + gl.getshaderinfolog(vs)); console.error('fs info-log: ' + gl.getshaderinfolog(fs)); } } khr_parallel_shader_compile for non-blocking compile/link status while we've described a pattern to allow browsers to compile and link in parallel, normally...

WebGL: 2D and 3D graphics for the web - Web APIs
guides and tutorials below, you'll find an assortment of guides to help you learn webgl concepts and tutorials that offer step-by-step lessons and examples.
... tutorials webgl tutorial a beginner's guide to webgl core concepts.
... webgl by example a series of live samples with short explanations that showcase webgl concepts and capabilities.

Taking still photos with WebRTC - Web APIs
once the stream is linked to the <video> element, we start it playing by calling htmlmediaelement.play().
...lled when the click event is issued: startbutton.addeventlistener('click', function(ev){ takepicture(); ev.preventdefault(); }, false); this method is simple enough: it just calls our takepicture() function, defined below in the section capturing a frame from the stream, then calls event.preventdefault() on the received event to prevent the click from being handled more than once.
... once the canvas contains the captured image, we convert it to png format by calling htmlcanvaselement.todataurl() on it; finally, we call photo.setattribute() to make our captured still box display the image.

WebRTC API - Web APIs
webrtc concepts and usage webrtc serves multiple purposes; together with the media capture and streams api, they provide powerful multimedia capabilities to the web, including support for audio and video conferencing, file exchange, screen sharing, identity management, and interfacing with legacy telephone systems including support for sending dtmf (touch-tone dialing) signals.
...once a connection has been established and opened using rtcpeerconnection, media streams (mediastreams) and/or data channels (rtcdatachannels) can be added to the connection.
...once set it can't be changed.

Using bounded reference spaces - Web APIs
unction onactivatexrbutton(event) { if (!xrsession) { navgator.xr.requestsession("immersive-vr"), { requiredfeatures: ["local-floor"], optionalfeatures: ["bounded-floor"] }).then((session) => { xrsession = session; startsessionanimation(); }); } } this function, called when the user clicks on a button to start the xr experience, works as usual, exiting at once if a session is already in place, then requesting a new session using immersive-vr mode.
... once the session has been created, our startsessionanimation() function can try to establish a bounded-floor reference space, and if it fails to do so it can then fall back to requesting a local-floor reference space instead (in which we will have to handle boundaries ourselves).
... in either case, once a reference space has been created, it's handed off to a function called onrefspacecreated(), which takes over the process of setting up the space for use.

Geometry and reference spaces in WebXR - Web APIs
however, in order to provide the ability to present scenes in true 3d using xr headsets and other such equipment, webxr has additional concepts that must be understood.
... in webxr, the fundamental concept of a space—as in, a coordinate space in which a scene takes place—is represented by an instance of xrspace.
... once created, an xrreferencespace guarantees a certain level of support for motion and orientation tracking, and provides a mechanism for obtaining an xrviewerpose from which you can get a matrix which represents the position and facing direction of the space relative to the world space, if the space represents a viewer such as the user's headset, an observer's headset, or a virtual camera.

Spaces and reference spaces: Spatial tracking in WebXR - Web APIs
note: this article presumes that you are familiar with the concepts introduced in geometry and reference spaces in webxr: that is, the basics of 3d coordinate systems, as well as webxr spaces, reference spaces, and how reference spaces are used to create local coordinate systems for individual objects or movable components within a scene.
... poses once your reference space or spaces are established for the various key objects in the scene, you will have times when you need to describe another position relative to the origin of a particular reference space.
... once the xr hardware begins providing tracking information, it will continue to do so until the xr session is clsoed.

WindowOrWorkerGlobalScope.setTimeout() - Web APIs
the settimeout() method of the windoworworkerglobalscope mixin (and successor to window.settimeout()) sets a timer which executes a function or specified piece of code once the timer expires.
... timeouts throttled to ≥ 4ms in modern browsers, settimeout()/setinterval() calls are throttled to a minimum of once every 4 ms when successive calls are triggered due to callback nesting (where the nesting level is at least a certain depth), or after certain number of successive intervals.
... timeouts in inactive tabs throttled to ≥ 1000ms to reduce the load (and associated battery usage) from background tabs, timeouts are throttled to firing no more often than once per second (1,000 ms) in inactive tabs.

system - CSS: Cascading Style Sheets
once the end of the list of symbols is reached, it will loop back to the beginning and start over.
...once the system has looped through all the specified symbols, it will fall back.
...once outside of the range, the rest of the counter representations will be based on the decimal style, which is the fall back.

Testing media queries programmatically - CSS: Cascading Style Sheets
once you've created a mediaquerylist object, you can check the result of the query or receive notifications when the result changes.
... for example, to set up a query list that determines if the device is in landscape or portrait orientation: const mediaquerylist = window.matchmedia("(orientation: portrait)"); checking the result of a query once you've created your media query list, you can check the result of the query by looking at the value of its matches property: if (mediaquerylist.matches) { /* the viewport is currently in portrait orientation */ } else { /* the viewport is not currently in portrait orientation, therefore landscape */ } receiving query notifications if you need to be aware of changes to the evaluated result...
...} // run the orientation change handler once.

background - CSS: Cascading Style Sheets
the background shorthand css property sets all background style properties at once, such as color, image, origin and size, or repeat method.
...if included once, it sets both background-origin and background-clip.
... accessibility concerns browsers do not provide any special information on background images to assistive technology.

break-after - CSS: Cascading Style Sheets
to determine if a break must be done, the following rules are applied: if any of the three concerned values is a forced break value (always, left, right, page, column, or region), it has precedence.
... if any of the three concerned values is an avoid break value (avoid, avoid-page, avoid-region, or avoid-column), no such break will be applied at that point.
... once forced breaks have been applied, soft breaks may be added if needed, but not on element boundaries that resolve in a corresponding avoid value.

break-before - CSS: Cascading Style Sheets
to determine if a break must be done, the following rules are applied: if any of the three concerned values is a forced break value (always, left, right, page, column, or region), it has precedence.
... if any of the three concerned values is an avoid break value (avoid, avoid-page, avoid-region, or avoid-column), no such break will be applied at that point.
... once forced breaks have been applied, soft breaks may be added if needed, but not on element boundaries that resolve in a corresponding avoid value.

break-inside - CSS: Cascading Style Sheets
to determine if a break must be done, the following rules are applied: if any of the three concerned values is a forced break value (always, left, right, page, column, or region), it has precedence.
... if any of the three concerned values is an avoid break value (avoid, avoid-page, avoid-region, or avoid-column), no such break will be applied at that point.
... once forced breaks have been applied, soft breaks may be added if needed, but not on element boundaries that resolve in a corresponding avoid value.

<display-box> - CSS: Cascading Style Sheets
please note that the css display level 3 spec defines how the contents value should affect "unusual elements" — elements that aren’t rendered purely by css box concepts such as replaced elements.
...see the accessibility concerns section below for more details.
... accessibility concerns current implementations in most browsers will remove from the accessibility tree any element with a display value of contents.

Audio and Video Delivery - Developer guides
here's a trick that stops the download at once: var mediaelement = document.queryselector("#mymediaelementid"); mediaelement.removeattribute("src"); mediaelement.load(); by removing the media element's src attribute and invoking the load() method, you release the resources associated with the video, which stops the network download.
...the sources are tried in the order in which they appear, and once one loads successfully, the remaining sources aren't tried at all.
... streaming media tutorials live streaming web audio and video live streaming technology is often employed to relay live events such as sports, concerts and more generally tv and radio programmes that are output live.

Rich-Text Editing in Mozilla - Developer guides
once designmode has been set to "on", the document becomes a rich-text editing area and the user can type into it as if it were a textarea.
... event handling disabled a further difference for mozilla is that once a document is switched to designmode, all events on that particular document are disabled.
... once designmode is turned off however (as this now seems possible in mozilla 1.5) the events become active again.

Index - Developer guides
dia, events this article provides: a basic guide to creating a cross-browser html5 audio player with all the associated attributes, properties, and events explained a guide to custom controls created using the media api 10 live streaming web audio and video guide, adaptive streaming live streaming technology is often employed to relay live events such as sports, concerts and more generally tv and radio programmes that are output live.
...once we're ready for wider adoption the information from wiki.mozilla.org will be moved here, updated and expanded.
... 41 the web open font format (woff) fonts, needsmobilebrowsercompatibility, woff woff (the web open font format) is a web font format developed by mozilla in concert with type supply, letterror, and other organizations.

Introduction to Web development - Developer guides
html elements reference guide — a comprehensive guide to html elements with details on how browsers support them css getting started with css — an absolute beginners guide to css covers basic concepts and fundamentals css reference guide — a complete guide to css with details on the level of gecko/firefox support for each.
... common css questions — common questions and answers for beginners intermediate css concepts — grouping, pseudo-classes and more.
... advanced learning advanced javascript — john resig's guide to advanced javascript crockford on advanced javascript — a three part video series on advanced javascript concepts javascript garden — documentation of the most quirky parts of javascript.

Writing forward-compatible websites - Developer guides
targeting hacks at old versions of browsers whose current versions no longer have the bug you're relying on for your hack is ok; once a browser has fixed bug x, you can know for certain that all releases that had bug x also had bug y and use the presence of bug x to target workarounds for bug y.
...and once the feature is standardized, the prefixed version is likely to be removed.
... once a browser has shipped a feature unprefixed, however, you can use the prefixed version to target old releases by making sure to always use the unprefixed version of the feature when available.

<abbr>: The Abbreviation element - HTML: Hypertext Markup Language
you can use <abbr> in concert with <dfn> to establish definitions for terms which are abbreviations or acronyms.
... html <p><dfn id="html"><abbr title="hypertext markup language">html</abbr> </dfn> is a markup language used to create the semantics and structure of a web page.</p> <p>a <dfn id="spec">specification</dfn> (<abbr title="specification">spec</abbr>) is a document that outlines in detail how a technology or api is intended to function and how it is accessed.</p> result accessibility concerns spelling out the acronym or abbreviation in full the first time it is used on a page is beneficial for helping people understand it, especially if the content is technical or industry jargon.
... example <p>javascript object notation (<abbr>json</abbr>) is a lightweight data-interchange format.</p> this is especially helpful for people who are unfamiliar with the terminology or concepts discussed in the content, people who are new to the language, and people with cognitive concerns.

<img>: The Image Embed element - HTML: Hypertext Markup Language
security and privacy concerns although <img> elements have innocent uses, they can have undesirable consequences for user security and privacy.
... see referer header: privacy and security concerns for more information and mitigations.
... accessibility concerns authoring meaningful alternate descriptions an alt attribute's value should clearly and concisely describe the image's content.

<main> - HTML: Hypertext Markup Language
<main> doesn't contribute to the document's outline; that is, unlike elements such as <body>, headings such as <h2>, and such, <main> doesn't affect the dom's concept of the structure of the page.
...</p> </article> </main> <!-- other content --> accessibility concerns landmark the <main> element behaves like a main landmark role.
...prefer using the <main> element over declaring role="main", unless there are legacy browser support concerns.

<script>: The Script element - HTML: Hypertext Markup Language
nonce a cryptographic nonce (number used once) to whitelist scripts in a script-src content-security-policy.
... the server must generate a unique nonce value each time it transmits a policy.
... it is critical to provide a nonce that cannot be guessed as bypassing a resource's policy is otherwise trivial.

<style>: The Style Information element - HTML: Hypertext Markup Language
nonce a cryptographic nonce (number used once) used to whitelist inline styles in a style-src content-security-policy.
... the server must generate a unique nonce value each time it transmits a policy.
... it is critical to provide a nonce that cannot be guessed as bypassing a resource’s policy is otherwise trivial.

<table>: The Table element - HTML: Hypertext Markup Language
th> <th>lemon</th> <th>orange</th> </tr> <tr> <td>green</td> <td>yellow</td> <td>orange</td> </tr> </table> <p>simple table with caption</p> <table> <caption>awesome caption</caption> <tr> <td>awesome data</td> </tr> </table> table { border-collapse: collapse; border-spacing: 0px; } table, th, td { padding: 5px; border: 1px solid black; } accessibility concerns captions by supplying a <caption> element whose value clearly and concisely describes the table's purpose, it helps the people decide if they need to read the rest of the table content or skip over it.
... this helps people navigating with the aid of assistive technology such as a screen reader, people experiencing low vision conditions, and people with cognitive concerns.
...in addition to helping people who use assistive technology understand the table's content, this may also benefit people with cognitive concerns who may have difficulty understanding the associations the table layout is describing.

accesskey - HTML: Hypertext Markup Language
alt + shift + key n/a edge n/a control + option + key control + option + shift + key google chrome alt + shift + key safari n/a opera 15+ alt + key control + alt + key opera 12 shift + esc opens a contents list which are accessible by accesskey, then, can choose an item by pressing key accessibility concerns in addition to poor browser support, there are numerous concerns with the accesskey attribute: an accesskey value can conflict with a system or browser keyboard shortcut, or assistive technology functionality.
... certain accesskey values may not be present on certain keyboards, especially when internationalization is a concern.
... accesskey values that rely on numbers may be confusing to individuals experiencing cognitive concerns, where the number doesn't have a logical association with the functionality it triggers.

About JavaScript - JavaScript
contrary to popular misconception, javascript is not "interpreted java".
...the basic syntax is intentionally similar to both java and c++ to reduce the number of new concepts required to learn the language.
...once an object has been constructed it can be used as a blueprint (or prototype) for creating similar objects.

Concurrency model and the event loop - JavaScript
runtime concepts the following sections explain a theoretical model.
... the processing of functions continues until the stack is once again empty.
... here is an example that demonstrates this concept (settimeout does not run immediately after its timer expires): const s = new date().getseconds(); settimeout(function() { // prints out "2", meaning that the callback is not called immediately after 500 milliseconds.

Expressions and operators - JavaScript
bitwise logical operators conceptually, the bitwise logical operators work as follows: the operands are converted to thirty-two-bit integers and expressed by a series of bits (zeros and ones).
... for example, if a is a 2-dimensional array with 10 elements on a side, the following code uses the comma operator to update two variables at once.
... every syntactically valid expression resolves to some value but conceptually, there are two types of expressions: with side effects (for example: those that assign value to a variable) and those that in some sense evaluate and therefore resolve to a value.

Array.prototype.reduce() - JavaScript
description the reduce() method executes the callback once for each assigned value present in the array, taking four arguments: accumulator currentvalue currentindex array the first time the callback is called, accumulator and currentvalue can be one of two values.
...'d', 'd', 'd'] let myorderedarray = myarray.reduce(function (accumulator, currentvalue) { if (accumulator.indexof(currentvalue) === -1) { accumulator.push(currentvalue) } return accumulator }, []) console.log(myorderedarray) replace .filter().map() with .reduce() using array.filter() then array.map() traverses the array twice, but you can achieve the same effect while traversing only once with array.reduce(), thereby being more efficient.
... (if you like for loops, you can filter and map while traversing once with array.foreach()).

Array.prototype.forEach() - JavaScript
the foreach() method executes a provided function once for each array element.
... description foreach() calls a provided callback function once for each element in an array in ascending order.
...(see this example, below.) foreach() executes the callback function once for each array element; unlike map() or reduce() it always returns the value undefined and is not chainable.

Promise.prototype.finally() - JavaScript
this provides a way for code to be run whether the promise was fulfilled successfully or rejected once the promise has been dealt with.
... description the finally() method can be useful if you want to do some processing or cleanup once the promise is settled, regardless of its outcome.
... the finally() method is very similar to calling .then(onfinally, onfinally) however there are a couple of differences: when creating a function inline, you can pass it once, instead of being forced to either declare it twice, or create a variable for it a finally callback will not receive any argument, since there's no reliable means of determining if the promise was fulfilled or rejected.

TypedArray.prototype.forEach() - JavaScript
the foreach() method executes a provided function once per array element.
... description the foreach() method executes the provided callback once for each element present in the typed array in ascending order.
... foreach() executes the callback function once for each typed array element; unlike every() and some() it, always returns the value undefined.

yield - JavaScript
once paused on a yield expression, the generator's code execution remains paused until the generator's next() method is called.
... each time the generator's next() method is called, the generator resumes execution, and runs until it reaches one of the following: a yield, which causes the generator to once again pause and return the generator's new value.
... function* countapplesales () { let salelist = [3, 7, 5] for (let i = 0; i < salelist.length; i++) { yield salelist[i] } } once a generator function is defined, it can be used by constructing an iterator as shown.

do...while - JavaScript
the condition is evaluated after executing the statement, resulting in the specified statement executing at least once.
... syntax do statement while (condition); statement a statement that is executed at least once and is re-executed each time the condition evaluates to true.
... examples using do...while in the following example, the do...while loop iterates at least once and reiterates until i is no longer less than 5.

Handling media support issues in web content - Web media technologies
a similar concept can be applied to still images; if an image you wish to present is very large and may take time to download (especially for slower devices or connections), you can offer a lower-resolution or alternate version that will be displayed until the full-quality version is available to be displayed.
... poster frames for video progressive images images—whether embedded using <img> or <picture>—don't support a concept similar to poster frames.
... once your image has been converted to progressive form, you can simply use it as usual.

The "codecs" parameter in common media types - Web media technologies
as noted elsewhere, this format was once commonly used on the web but no longer is, since it required a plugin to use.
...see yuv in digital video concepts for details on how the yuv color system works.
...the following table lists permitted values; see chroma subsampling in digital video concepts for additional information about this topic and others.

Media type and format guide: image, audio, and video content - Web media technologies
guides concepts digital audio concepts an introduction to how audio is converted into digital form and stored for use by computers.
... it explains basic concepts about how audio is sampled, as well as concepts such as sample rate, audio frames, and audio compression.
... digital video concepts a guide to fundamental concepts involved with digital video as used on the web, including basics about color formats, chroma subsampling, how human perception influences video coding, and so forth.

Progressive web app structure - Progressive web apps (PWAs)
the most popular approach is the "app shell" concept, which mixes ssr and csr in exactly the way described above, and in addition follows the "offline first" methodology which we will explain in detail in upcoming articles and use in our example application.
... app shell the app shell concept is concerned with loading a minimal user interface as soon as possible and then caching it so it is available offline for subsequent visits before then loading all the contents of the app.
... different concept: streams an entirely different approach to server- or client-side rendering can be achieved with the streams api.

Introduction to progressive web apps - Progressive web apps (PWAs)
it's just a shorthand used initially by google for the concept of creating a flexible, adaptable app using only web technologies.
... it's not a brand new concept—such ideas have been revisited many times on the web platform with various approaches in the past.
... browse any kind of content the user has previously visited at least once, even under situations of poor connectivity.

Structural overview of progressive web apps - Progressive web apps (PWAs)
the most popular approach is the app shell concept, which mixes ssr and csr in exactly the way described above, and in addition follows the "offline first" methodology which we will explain in detail in upcoming articles and use in our example application.
... the app shell concept the app shell concept is concerned with loading a minimal user interface and content as soon as possible, caching it so it's available offline for subsequent visits before then loading the remainder of the app's contents.
...once it's available, however, it will be the fastest way to serve your app's content.

An Overview - XSLT: Extensible Stylesheet Language Transformations
« transforming xml with xslt the extensible stylesheet language/transform is a very powerful language, and a complete discussion of it is well beyond the scope of this article, but a brief discussion of some basic concepts will be helpful in understanding the description of netscape's capabilities that follows.
...the tree is an abstract datatype, a conceptual model which can be implemented in various ways depending on the parser and the processor.
...the only requirements concern the disposition of objects in the tree, their properties, and their relationships.

Porting the Library Detector - Archive of obsolete content
once the list is built, the switchlibraries() function constructs a xul statusbarpanel element for each library it found, populates it with the icon at the corresponding chrome:// url, and adds it to the box.
...ibrarylist) { if (!worker.tab.libraries) { worker.tab.libraries = []; } librarylist.foreach(function(library) { if (worker.tab.libraries.indexof(library) == -1) { worker.tab.libraries.push(library); } }); if (worker.tab == tabs.activetab) { updatewidgetview(worker.tab); } }); } }); the content script is executed once for every window.onload event, so it will run multiple times when a single page containing multiple iframes is loaded.

page-worker - Archive of obsolete content
this may take one of the following values: "start": load content scripts immediately after the document element for the page is inserted into the dom, but before the dom content itself has been loaded "ready": load content scripts once dom content has been loaded, corresponding to the domcontentloaded event "end": load content scripts once all the content (dom, js, css, images) for the page has been loaded, at the time the window.onload event fires this property is optional and defaults to "end".
...this may have one of the following values: "start": load content scripts immediately after the document element for the page is inserted into the dom, but before the dom content itself has been loaded "ready": load content scripts once dom content has been loaded, corresponding to the domcontentloaded event "end": load content scripts once all the content (dom, js, css, images) for the page has been loaded, at the time the window.onload event fires contentscriptoptions read-only value exposed to content scripts under self.options property.

tabs - Archive of obsolete content
tabs.open({ url: "http://www.mysite.com", inbackground: true }); // open a new tab as an app tab and do something once it's open.
...it has one of four possible values: "uninitialized": the tab's document is not yet loading "loading": the tab's document is still in the process of loading "interactive": the tab's document has loaded and is parsed, but resources such as images and stylesheets may still be loading "complete": the tab's document and all resources are fully loaded once a tab's readystate has entered "interactive", you can retrieve properties such as the document's url.

content/loader - Archive of obsolete content
usage the module exports a constructor for the loader object, which inherits on(), once(), and removelistener() functions that enable its users to listen to events.
...this may take one of the following values: "start": load content scripts immediately after the document element for the page is inserted into the dom, but before the dom content itself has been loaded "ready": load content scripts once dom content has been loaded, corresponding to the domcontentloaded event "end": load content scripts once all the content (dom, js, css, images) for the page has been loaded, at the time the window.onload event fires contentscriptoptions read-only value exposed to content scripts under self.options property.

content/symbiont - Archive of obsolete content
this may take one of the following values: "start": load content scripts immediately after the document element for the page is inserted into the dom, but before the dom content itself has been loaded "ready": load content scripts once dom content has been loaded, corresponding to the domcontentloaded event "end": load content scripts once all the content (dom, js, css, images) for the page has been loaded, at the time the window.onload event fires this property is optional and defaults to "end".
...this may have one of the following values: "start": load content scripts immediately after the document element for the page is inserted into the dom, but before the dom content itself has been loaded "ready": load content scripts once dom content has been loaded, corresponding to the domcontentloaded event "end": load content scripts once all the content (dom, js, css, images) for the page has been loaded, at the time the window.onload event fires contentscriptoptions read-only value exposed to content scripts under self.options property.

net/xhr - Archive of obsolete content
usage security concerns by default, the xmlhttprequest object grants full access to any protocol scheme, which means that it can be used to read from (but not write to) the host system's entire filesystem.
...for more information about xmlhttprequest objects, see the mdn page on using xmlhttprequest and the security concerns section in this page.

places/bookmarks - Archive of obsolete content
save(bookmarks).on("data", function (saved, input) { // a data event is called once for each item saved, as well // as implicit items, like `group` console.log(input === group || ~bookmarks.indexof(input)); // true }).on("end", function (saves, inputs) { // like the previous example, the "end" event returns an // array of all of our updated saves.
... let { bookmark, group, save } = require("sdk/places/bookmarks"); let group = group({ title: "my group" }); let bookmarks = [ bookmark({ title: "mozilla", url: "http://mozilla.com", group: group }), bookmark({ title: "w3", url: "http://w3.org", group: group }) ]; save(bookmarks).on("data", function (item) { // this function will be called three times: // once for each bookmark saved // once for the new group specified implicitly // as the parent of the two items }); the data event is also called for search requests, with each result being passed individually into its own data event.

ui/button/action - Archive of obsolete content
once() assign a listener to the first occurrence only of an event emitted by the button.
...for example, this code is equivalent to once(): button.on("click", handleclick) function handleclick(state) { console.log("button '" + state.label + "' was clicked"); button.removelistener("click", handleclick); } parameters event : string the event to listener is listening for.

ui/button/toggle - Archive of obsolete content
once() assign a listener to the first occurrence only of an event emitted by the button.
...for example, this code is equivalent to once(): button.on("click", handleclick) function handleclick(state) { console.log("button '" + state.label + "' was clicked"); button.removelistener("click", handleclick); } parameters event : string the event to listener is listening for.

jpm - Archive of obsolete content
once you've supplied a value or accepted the default for these properties, you'll be shown the complete contents of "package.json" and asked to accept it.
... once you have built an xpi file, you can distribute your add-on by submitting it to addons.mozilla.org.

Getting Started (jpm) - Archive of obsolete content
once you've done that, you'll be looking at a command prompt.
... once you've supplied a value or accepted the default for these properties, you'll be shown the complete contents of "package.json" and asked to accept it.

View Source for XUL Applications - Archive of obsolete content
linenumber (optional) the line number to focus on once the source has loaded.
... alinenumber (optional) the line number to focus on once the source has loaded.

Enhanced Extension Installation - Archive of obsolete content
since our needs and the needs of other applications may vary in the future, since we've already effectively generalized the concept of an install location, we can make this set configurable by applications and extensions.
...at the end of the process once everything has succeeded the {guid}-trash folder is removed.

Migrating raw components to add-ons - Archive of obsolete content
they will be registered the first time firefox is run once your add-on is installed.
... automatic installation once you have an add-on packaged, users can install it by visiting your site and giving the add-on permission to install.

Appendix: What you should know about open-source software licenses - Archive of obsolete content
as far as the author is concerned, this is an unrelated application of the work.
... copyleft is not required a common misconception regarding open source is that any modification made to open-source code must also be released as open source.

Chapter 3: Introduction to XUL—How to build a more intuitive UI - Archive of obsolete content
because html was originally conceived as a language for marking up documents, specifically web pages, it is inevitably lacking in functionality for marking up applications.
... xul, on the other hand, was conceived from the ground up as a markup language for user interfaces, and makes it possible to insert ui components with sophisticated features just by writing tags, without any particular scripting.

Connecting to Remote Content - Archive of obsolete content
xpath can also be used to extract information from web pages once they load, along with the page load interception techniques discussed previously.
... after installation, you can find a tamper data menu item in the menu bar: tools > tamper data or view > sidebar > tamper data once you open the tamper data view, all requests and responses will begin to appear in it.

Setting Up a Development Environment - Archive of obsolete content
this is where all the resulting build files will be created, and where you'll find the extension xpi file once you get it to build.
...once you're testing and debugging your code, you'll find that constantly building and installing an xpi can be very tedious.

The Essentials of an Extension - Archive of obsolete content
the js function will be called once the user clicks on the menu item in the hello world menu.
... once you're done, you can look at this reference solution: hello world 2.

Useful Mozilla Community Sites - Archive of obsolete content
your extension begins in a sandbox with limited access, and once you nominate it an editor will review it and see if it is appropriate for the public amo site, where everyone can see it and install it.
...you just need to upload a new version of your extension, and once it's approved it will be pushed as an update to all your users.

Performance best practices in extensions - Archive of obsolete content
this makes it easy to load chunks of your extension on the fly as needed, instead of loading everything all at once.
... avoid dom mutation event listeners dom mutation event listeners are extremely expensive and, once added to a document even briefly, significantly harm its performance.

Creating a dynamic status bar extension - Archive of obsolete content
concepts covered in the previous sample won't be reiterated here; instead, refer to the downloadable sample code or to the previous sample for further details.
...we end up reloading data from each of the windows once in 10 minutes - fixing this by creating a js component responsible for communication with the server is a good idea for one of the future articles startup: function() { this.refreshinformation(); window.setinterval(this.refreshinformation, 10*60*1000); }, this starts by calling our refreshinformation() function, which is responsible for fetching and displaying stock ticker information in the...

Creating a status bar extension - Archive of obsolete content
many of the concepts introduced here apply to any xul-based application; however, to keep from getting completely overwhelmed, we're going to focus specifically on firefox.
...this is accomplished by the following line of xml: <overlay id="status-bar-sample-1-overlay" xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"> once that's accomplished, we can describe our user interface.

Inner-browsing extending the browser navigation paradigm - Archive of obsolete content
this article discusses the concept of inner-browsing and possible approaches for its implementation.
...data loader component this component is a simple javascript function that sets the src attribute of the hidden iframe, causing it to load an url (i.e., by establishing a request on the server side): /* triggers the iframe to retrieve new data */ function retrievedata() { bridgeframe.src = dataurl; } once a web page is loaded into the iframe, the data binder will be able to get the data from the iframe's page and set the data into the main page's context.

MMgc - Archive of obsolete content
it may be multiply instantiated; you may have multiple instances of the garbage collector running at once.
...this is an unfortunate artifact of the existing code base, the avm+ is relatively clean and its reachability graph consists of basically 2 gc roots (the avmcore and urlstreams) but the avm- has a bunch (currently includes securitycallbackdata, moviecliploader, camerainstance, fappacket, microphoneinstance, csoundchannel, urlrequest, responceobject, urlstream and urlstreamsecurity).

Notes on HTML Reflow - Archive of obsolete content
the reflow tree work, which will remove several commands from the queue at once.) a path is built from the target frame to the root frame and stored in the reflow command.
...were we to process each individually, the text widget would be flowed once for each keystroke, which would be wasteful if the latency of an individual reflow exceeds the speed at which text is being typed.

Getting Started - Archive of obsolete content
once you've done this, insert the information as above, and scroll down.
...once you have put the files in the zip folder, rename it to myskin.jar triggering the install from the web to install the theme's jar file directly from the web, you need to run some javascript.

Getting Started - Archive of obsolete content
delete the bolded text: original skin,install,url,jar:resource:/chrome/classic.jar!/skin/classic/global/ modified skin,install,url,resource:/chrome/classic/skin/classic/global/ once you have made these modifications, save them and run mozilla.
...once the zip is created, rename it to myskin.jar contents of myskin.jar contents.rdf preview.png \navigator\...

Creating a Skin for Firefox/Getting Started - Archive of obsolete content
once you've done this, insert the information as above, and scroll down.
...once you have put the files in the zip folder, rename it to my_theme.jar triggering the install from the web to install the theme's jar file directly from the web, you need to run some javascript.

Dehydra Function Reference - Archive of obsolete content
decl is a variable type input_end() called once at the end of the c++ source file before the compiler quits.
...includes are guarded so a file is only included once and subsequent include calls are ignored.

Drag and Drop - Archive of obsolete content
once this function is called, a drag has started.
...an array is used because you might want to drag several objects at once, such as a set of files.

Document Loading - From Load Start to Finding a Handler - Archive of obsolete content
nsdocumentopeninfo implements nsistreamlistener and proxies the nsistreamlistener calls over to the "real" stream listener once one is chosen.
...this way, once we know what type we've managed to get we can attempt to redispatch it.

Repackaging Firefox - Archive of obsolete content
once you have all the ingredients, the customization process is quite easy: download the firefox installer.
... repackaging firefox once you have all the required pieces in place, all you need to do is launch the repackager tool and fill in the fields to set up your customized installers.

Introducing the Audio API extension - Archive of obsolete content
once the buffer is full, the event mozaudioavailable is triggered.
...audiooutput.mozsetup(2, 44100); once this is done, the samples need to be created.

Modularization techniques - Archive of obsolete content
you don't have to use them in your interfaces unless you're concerned with com compatibility.
... ns_isample_iid); int main(int argc, char *argv[]) { nsifactory *factory; getsamplefactory(&factory); nsisample *sample; nsresult res = factory->createinstance(null, kisampleiid, (void **) &sample); if (res == ns_ok) { sample->hello(); ns_release(sample); } return 0; } moving to a dynamically linked library implementing a dll once you've set a factory, moving it to a dll is a relatively trivial thing.

Mozilla Application Framework in Detail - Archive of obsolete content
customized xul applications with significant business logic can be written once, and used on the range of platforms that exist within the organization.
...with gecko, developers seeking a streamlined way to create and distribute web-based services across multiple platforms and devices can write once to w3c standards and their content and web applications will be accessible from across computing platforms and devices.

Tuning Pageload - Archive of obsolete content
the reason for this is that nscssframeconstructor is most efficient when doing a bunch of stuff at once instead of constructing rendering objects for one dom node at a time.
...once the backoff count is reached, no more rendering model construction till after the whole page is parsed.

Using cross commit - Archive of obsolete content
using the script quick overview there are a couple of common ways to use cross-commit: land something simultaneously on the trunk and mozilla_1_8_branch # modify the files (probably by applying the patch) patch -p0 < ~/caret.patch # commit on trunk and branch at once # make sure to use -m "commit message" when doing so tools/cross-commit -m "fix some sort of security bug" layout/base/nscaret.h land something on two other branches that has already landed on the trunk # update to the first branch you want to land on cvs update -rmozilla_1_8_branch layout/base/nscaret.h # modify the files (probably by applying the patch) patch -p0 < ~/caret.patch # c...
...ommit on all the branches at once # make sure to use -m "commit message" when doing so tools/cross-commit --moz18 --branch mozilla_1_8_0_branch -m "fix some sort of security bug" layout/base/nscaret.h notes note that you must use a -m option with a cvs checkin message.

Elements - Archive of obsolete content
once the binding is attached, these methods and properties can be invoked directly from the bound element.
...like methods, once the binding is attached, the property can be obtained directly from the bound element.

Mac stub installer - Archive of obsolete content
once you have the mac installer built and ready to debug you may want to debug the xpinstall engine in the context of the installer rather than in the context of the browser.
... once you add the section to the packages-mac file the release automation will automatically generate an xpi for your module with a dummy install.js.

execute - Archive of obsolete content
executing installed files note: if the file you wish to execute is one you are installing (as opposed to an installer executable that you plan to delete once it runs), then use the execute method on the file object instead.
...the install object's execute method, on the other hand, deletes the executable from its temporary location once it has finished.

Dynamically modifying XUL-based user interface - Archive of obsolete content
it explains the concept of dom documents, demonstrates a few simple examples of using dom calls to perform basic manipulations on a document, and then demonstrates working with anonymous xbl content using mozilla-specific methods.
...once you have an anonymous node, you can use regular dom methods to navigate and manipulate the rest of the nodes of that binding.

OpenClose - Archive of obsolete content
closing menus menus will close automatically once the user has made a selection from the menu.
...once the menu is open, the keyboard can be used to navigate and select items as usual.

Actions - Archive of obsolete content
one difference is that this content is only generated once, not for every result.
...for example, if the example were modified to the following: <action> <toolbar> <button uri="?relateditem" label="?relateditem"/> </toolbar> </action> here, only the button would be repeated for each result; the toolbar will only be generated once.

Building Trees - Archive of obsolete content
en> <treeitem uri="rdf:*"> <treerow> <treecell label="rdf:http://purl.org/dc/elements/1.1/title"/> <treecell label="rdf:http://purl.org/dc/elements/1.1/date"/> </treerow> </treeitem> </treechildren> </template> </tree> note: the tree columns (treecols) are declared outside the template as static content, since they only need to be declared once.
...once the row height is changed, we can see the full photos.

Filtering - Archive of obsolete content
even though the same datasource is used, it will only be loaded once and both templates will be notified when the data has loaded.
...another workaround is to just rebuild the template once the data has been loaded.

RDF Modifications - Archive of obsolete content
once we do add it to the container with another rdf assertion, the process described above is applied again and this time it may match.
...first, once the builder reaches the content statement, it checks what the container or reference variable is, in this case ?start, as specified by the uri attribute.

Rule Compilation - Archive of obsolete content
once the template builder has compiled the rules, query processing and content generation can begin.
...once done, the correct length can be returned.

Template Builder Interface - Archive of obsolete content
however, one thing to watch out for is that non-xul elements do not have their content generated lazily so all of the content will be generated at once.
...in this case, the template will be rebuilt automatically as you can set all of the datasources at once with this method of changing datasources.

XML Templates - Archive of obsolete content
the element with the uri attribute and its children will be copied once for each result.
... any elements between the action element and this element are only copied once.

Document Object Model - Archive of obsolete content
once we have an indication of whether it is checked or not, we can use the state to perform the search.
... var box = document.getelementbyid('somebox'); var flex = box.flex; var box2 = document.getelementbyid('anotherbox'); box2.flex = 2; once you have a reference to an element, you can call the properties of that element.

Input Controls - Archive of obsolete content
radio buttons can be used for a similar purpose when there are a set of them and only one can be selected at once.
...only one of the radio buttons in a radio group can be selected at once.

Templates - Archive of obsolete content
content earlier will only be generated once whereas content inside will be generated for each resource.
...if the uri attribute is placed on an element lower in the element tree, the elements outside are only created once.

Tree View Details - Archive of obsolete content
the code above uses a brute force method which simply iterates over the rows looking for one, returning true if a row exists with the same level and false once it finds a row that has a lower level.
... this.treebox.rowcountchanged(idx + 1, toinsert.length); } this.treebox.invalidaterow(idx); }, getimagesrc: function(idx, column) {}, getprogressmode : function(idx,column) {}, getcellvalue: function(idx, column) {}, cycleheader: function(col, elem) {}, selectionchanged: function() {}, cyclecell: function(idx, column) {}, performaction: function(action) {}, performactiononcell: function(action, index, column) {}, getrowproperties: function(idx, prop) {}, getcellproperties: function(idx, column, prop) {}, getcolumnproperties: function(column, element, prop) {}, }; function init() { document.getelementbyid("elementlist").view = treeview; } ]]></script> </window> next, we'll look in more detail at the tree box object.

XPCOM Interfaces - Archive of obsolete content
for example, once we have a component, we can check if it implements nsisound, and, if so, we can play sound through it.
... call the function we need once you've done the first two steps, you can repeat the last step as often as necessary.

XUL element attributes - Archive of obsolete content
once the default sizes of elements in a box are calculated, the remaining space in the box is divided among the flexible elements, according to their flex ratios.
...elements outside will appear only once.

scrollbox - Archive of obsolete content
<vbox> <label value="01 four score and seven years ago "/> <label value="02 our fathers brought forth on "/> <label value="03 this continent, a new nation, "/> <label value="04 conceived in liberty, and "/> <label value="05 dedicated to the proposition "/> <label value="06 that all men are created equal."/> </vbox> the next bunch of labels is similar, but if the container doesn't give enough room for it, scroll bars will sprout out of nowhere and allow the user to scroll around the big content in the small view space.
... <vbox flex="1" style="overflow:auto"> <label value="01 four score and seven years ago "/> <label value="02 our fathers brought forth on "/> <label value="03 this continent, a new nation, "/> <label value="04 conceived in liberty, and "/> <label value="05 dedicated to the proposition "/> <label value="06 that all men are created equal."/> </vbox> the flex="1" above may or may not be needed, or even desired.

textbox - Archive of obsolete content
from gecko 1.9 to gecko 12.0 (firefox 12.0 / thunderbird 12.0 / seamonkey 2.9), the script code would actually execute twice, once in the context of the anonymous html <input> element and once in the context of the <textbox> element itself.
...from gecko 1.9 to gecko 12.0 (firefox 12.0 / thunderbird 12.0 / seamonkey 2.9), the script code would actually execute twice, once in the context of the anonymous html <input> element and once in the context of the <textbox> element itself.

Getting started with XULRunner - Archive of obsolete content
installing the application creates an os x application bundle: /library/frameworks/xul.framework/xulrunner-bin --install-app /<path>/<to>/myapp.zip once installed, you can run the application: /library/frameworks/xul.framework/xulrunner-bin "/applications/finkle/testapp.app/contents/resources/application.ini" you may run it without installing (but with the menu bar and dock icon missing) in os x by typing: /library/frameworks/xul.framework/xulrunner-bin "/<full path>/testapp/application.ini" note: the full path is required or a "error: co...
...once you've got an application that's ready for the world you'll love our article titled deploying xulrunner.

Archived Mozilla and build documentation - Archive of obsolete content
browsers, like internet explorer 4, that were built before the conception of w3c standards inherited many quirks.
...prism is based on a concept called site-specific browsers (ssb).

2006-12-01 - Archive of obsolete content
windows dde shell integration removal a call for responses or concerns regarding the removal of the dde shell integration.
... ff2 not responding to click on link concerns regarding ff 2.0 not responding to button or link clicks until the button or link is clicked a second time.

2006-10-27 - Archive of obsolete content
these were the following choices stated: search the filesystem for unneeded files delete or archive them, add a hard disk, move all or part of the concerned filesystem there move that tinderbox to a different machine with more empty disk space on october 23rd: nick responded to gavin and tony's posting.
... nick stated that the build engineers knew that there was a problem with the tinderbox and that they would be solving the problem by adding a hard disk, and moving all or part of the concerned filesystem there.

XEmbed Extension for Mozilla Plugins - Archive of obsolete content
once you've verified that the browser has the compatibility you require, you can modify your npp_getvalue call like so: nperror npp_getvalue(void *future, nppvariable variable, void *value) { nperror err = nperr_no_error; switch (variable) { case nppvpluginneedsxembed: *((prbool *)value) = pr_true; break; default: err = nperr_generic_error; } return err...
...; } once you have set those variables, it should be relatively easy to set up a plugin.

Table Reflow Internals - Archive of obsolete content
ed height during 3rd pass doesn't change height during 3rd pass initiator is the table containing the observer starts the 3rd pass reflow and sets a bit in the reflow state gives its block a computed height during 3rd pass could also be inside a cell which is an observer special height reflow optimizations only frames needing 3rd pass actually get it frames gettting a 3rd pass only get it once intro to paginated reflow when a reflowee's available height is constrained, it may not fit and need to either split/continue on the next page, or start on the next page.
...if it is incomplete, it will become the first-in-flow it will be the only frame among its continuations to ever balance or calc the cell map, and it only does this once table paginated reflow the table does a pass 2 reflow constraining both avail heights and widths.

Scratchpad - Archive of obsolete content
executing once you've written your code, select the code you want to run.
...once you've done this, the environment menu has a browser option; once that's selected, your scope is the entire browser rather than just the page content, as you will see from examining some globals: window /* [object chromewindow] */ gbrowser /* [object xulelement] */ the scratchpad execution context is set to browser when a snippet file has // -sp-context: browser on the first line.

Using SSH to connect to CVS - Archive of obsolete content
once you have entered a passphrase, ssh-keygen will create two files, ~/.ssh/id_dsa and ~/.ssh/id_dsa.pub do not sendid_dsa.
...only proceed with these steps once you are certain you can access cvs.mozilla.org from the open internet.

Reference - Archive of obsolete content
once that is done, the various code samples should be updated to reflect current practices and code if they cannot be written in a "version-neutral" manner.
...if downloading the stuff is your priority you are free to field ideas/concept to the devmo mailing list for discussion, and then actually code it (or find someone to do so).

Correctly Using Titles With External Stylesheets - Archive of obsolete content
authors will be most familiar with persistent stylesheets, of which any number may be applied to a document at once.
...once the user selects one of the alternate stylesheets, the preferred stylesheet will no longer be used, although the user can always re-select the preferred stylesheet.

Using the Right Markup to Invoke Plugins - Archive of obsolete content
here is an example of this usage, once again for the macromedia flash plugin: <object type="application/x-shockwave-flash" data="javascript-to-flash.swf" width="366" height="142" id="myflash"> <param name="movie" value="javascript-to-flash.swf" /> <param name="quality" value="high" /> <param name="swliveconnect" value="true" /> <p>you need flash -- get the latest version from <a href= "http://www.macromedia.com/do...
...once again, ie typically invokes the plugin by way of an object element used in conjunction with a classid attribute that points to an activex unique identifier.

XQuery - Archive of obsolete content
xquseme is a working proof-of-concept (so far tested on windows and linux with java installed; mac does not work) extension which allows one to perform xqueries on external urls, the currently loaded webpage (even if originally from poorly formed html), and/or xml (including well-formed xhtml) documents stored locally.
... however, use of the approach of the java firefox extension might be used to turn the above extension concept into an xpcom component (giving it access to all open windows), and for berkeley db xml, possibly implementing it in c++ instead, which is that database's original language of development.

Archive of obsolete content
case sensitivity in class and id names creating a dynamic status bar extension concepts covered in the previous sample won't be reiterated here; instead, refer to the downloadable sample code or to the previous sample for further details.
... creating a status bar extension many of the concepts introduced here apply to any xul-based application; however, to keep from getting completely overwhelmed, we're going to focus specifically on firefox.

Game distribution - Game development
benefits of html5 over native building games with html5 gives you extra advantages, such as: multiplatform bliss the technology itself is multiplatform, so you can write the code once and target multiple devices.
...the good thing is that you don't need a few separate teams working on the same game for different platforms — you can build it once and use tools like phonegap or cocoonio to package the game for native stores.

Desktop gamepad controls - Game development
first, we need an event listener to listen for the connection of the new device: window.addeventlistener("gamepadconnected", gamepadhandler); it's executed once, so we can create some variables we will need later on for storing the controller info and the pressed buttons: var controller = {}; var buttonspressed = []; function gamepadhandler(e) { controller = e.gamepad; output.innerhtml = "gamepad: " + controller.id; } the second line in the gamepadhandler function shows up on the screen when the device is connected: we can also show the id o...
...here's the code we've prepared in the create() function that is executed once when the new state is created: create() { // ...

Implementing game control mechanisms - Game development
the first one is needed for preloading required assets, create() is executed once the state had started, and update() is executed on every frame.
...} it will be created once at the start of the game, and will execute this.clickenclave() action assigned to it when clicked, but you can also use the mouse's pointer value in the update() function to make an action: update: function() { // ...

Plug-in Development Overview - Gecko Plugin API Reference
« previousnext » writing plug-ins once you decide what you want your plug-in to do, creating it is a simple process.
... building plug-ins once you have added the special code and additional files to make your plug-in scriptable as described in the previous section, the build process is quite straightforward.

Asynchronous - MDN Web Docs Glossary: Definitions of Web-related terms
for humans, e-mail is an asynchronous communication method; the sender sends an email and the recipient will read and reply to the message when it's convenient to do so, rather than doing so at once.
... software design asynchronous software design expands upon the concept by building code that allows a program to ask that a task be performed alongside the original task (or tasks), without stopping to wait for the task to complete.

Grid Cell - MDN Web Docs Glossary: Definitions of Web-related terms
it is the space between four intersecting grid lines and conceptually much like a table cell.
...d9480f; } .wrapper { display: grid; grid-template-columns: repeat(3,1fr); grid-auto-rows: 100px; } <div class="wrapper"> <div>one</div> <div>two</div> <div>three</div> <div>four</div> <div>five</div> </div> learn more property reference grid-template-columns grid-template-rows grid-auto-rows grid-auto-columns further reading css grid layout guide: basic concepts of grid layout definition of grid cells in the css grid layout specification ...

HTML - MDN Web Docs Glossary: Definitions of Web-related terms
brief history in 1990, as part of his vision of the web, tim berners-lee defined the concept of hypertext, which berners-lee formalized the following year through a markup mainly based on sgml.
... concept and syntax an html document is a plaintext document structured with elements.

Hoisting - MDN Web Docs Glossary: Definitions of Web-related terms
however, the concept can be a little confusing at first.
... conceptually, for example, a strict definition of hoisting suggests that variable and function declarations are physically moved to the top of your code, but this is not in fact what happens.

CSS and JavaScript accessibility best practices - Learn web development
hiding things there are many instances where a visual design will require that not all content is shown at once.
... other javascript accessibility concerns there are other things to be aware of when implementing javascript and thinking about accessibility.

What is accessibility? - Learn web development
people with mobility impairments these people have disabilities concerning movement, which might involve purely physical issues (such as loss of limb or paralysis), or neurological/genetic disorders that lead to weakness or loss of control in limbs.
...there is no need to learn all of the wcag — be aware of the major areas of concern, and use a variety of techniques and tools to highlight any areas that don't conform to the wcag criteria (see below for more).

Backgrounds and borders - Learn web development
if you discover a complex background property in a stylesheet, it might seem a little hard to understand as so many values can be passed in at once.
...this shorthand lets you set all of the different properties at once.

Pseudo-classes and pseudo-elements - Learn web development
once you know how to use them, you can look at the list to see if there is something which works for the task you are trying to achieve.
... once again the relevant mdn page for each selector is helpful in explaining browser support.

Sizing items in CSS - Learn web development
for example, if you want a full-page hero section to show before the rest of your content, making that part of your page 100vh high will push the rest of the content below the viewport, meaning that it will only appear once the document is scrolled.
...when you move onto css layout, sizing will become very important in mastering the different layout methods, so it is worth understanding the concepts here before moving on.

CSS building blocks - Learn web development
cascade and inheritance the aim of this lesson is to develop your understanding of some of the most fundamental concepts of css — the cascade, specificity, and inheritance — which control how css is applied to html and how conflicts are resolved.
... overflowing content in this lesson we will look at another important concept in css — overflow.

CSS layout - Learn web development
introduction to css layout this article will recap some of the css layout features we've already touched upon in previous modules — such as different display values — and introduce some of the concepts we'll be covering throughout this module.
... responsive design as more diverse screen sizes have appeared on web-enabled devices, the concept of responsive web design (rwd) has appeared: a set of practices that allows web pages to alter their layout and appearance to suit different screen widths, resolutions, etc.

How do I start to design my website? - Learn web development
once you have such a list, you need to prioritize.
...once you have that clear vision, you need to decide how and when to do it.

How do you upload your files to a web server? - Learn web development
here and there: local and remote view once connected, your screen should look something like this (we've connected to an example of our own to give you an idea): let's examine what you're seeing: on the center left pane, you see your local files.
... once you've found the correct remote directory to put your files in, to upload your files to the server you need to drag-and-drop them from the left pane to the right pane.

What is a URL? - Learn web development
prerequisites: you need to first know how the internet works, what a web server is and the concepts behind links on the web.
... summary with hypertext and http, url is one of the key concepts of the web.

Client-side form validation - Learn web development
this article leads you through basic concepts and examples of client-side form validation.
... once you have checked that the form is filled out correctly, the form can be submitted.

Sending form data - Learn web development
previous overview: forms once the form data has been validated on the client-side, it is okay to submit the form.
...we also look at some of the security concerns associated with sending form data.

Sending forms through JavaScript - Learn web development
if( file.dom.files[0] ) { reader.readasbinarystring( file.dom.files[0] ); } // if not, read the file once the user selects it.
... // text data is simpler // start a new part in our body's request data += "--" + boundary + "\r\n"; // say it's form data, and name it data += 'content-disposition: form-data; name="' + text.name + '"\r\n'; // there's a blank line between the metadata and the data data += '\r\n'; // append the text data to our body's request data += text.value + "\r\n"; // once we are done, "close" the body's request data += "--" + boundary + "--"; // define what happens on successful data submission xhr.addeventlistener( 'load', function( event ) { alert( 'yeah!

Test your skills: Basic controls - Learn web development
turn the first <fieldset>'s contents into a set of radio buttons — you should only be able to select one pony character at once.
... allow the user to pick multiple files at once.

Your first form - Learn web development
uxmatters is also a very thoughtful resource with good advice from basic best practices to complex concerns such as multi-page forms.
...with this text"> on the other hand, if you want to define a default value for a <textarea>, you put it between the opening and closing tags of the <textarea> element, like this: <textarea> by default this element is filled with this text </textarea> the <button> element the markup for our form is almost complete; we just need to add a button to allow the user to send, or "submit", their data once they have filled out the form.

Advanced text formatting - Learn web development
as confucius' quotes site says:</p> <p>it does not matter how slowly you go as long as you do not stop.</p> <p>i also love the concept of positive thinking, and the need to eliminate negative self talk (as mentioned in affirmations for positive thinking.)</p> </textarea> <div class="playable-buttons"> <input id="reset" type="button" value="reset"> <input id="solution" type="button" value="show solution"> </div> html { font-family: sans-serif; } h2 { font-size: 16px; } .a11y-label { margin: 0; text-align: right;...
...as <a href="http://www.brainyquote.com/quotes/authors/c/confucius.html"><cite>confucius\' quotes site</cite></a> says:</p>\n\n<blockquote cite="http://www.brainyquote.com/quotes/authors/c/confucius.html">\n <p>it does not matter how slowly you go as long as you do not stop.</p>\n</blockquote>\n\n<p>i also love the concept of positive thinking, and <q cite="http://www.affirmationsforpositivethinking.com">the need to eliminate negative self talk</q> (as mentioned in <a href="http://www.affirmationsforpositivethinking.com"><cite>affirmations for positive thinking</cite></a>.)</p>'; const solutionentry = htmlsolution; textarea.addeventlistener('input', updatecode); window.addeventlistener('load', updatecode); // s...

Video and audio content - Learn web development
a webm file containing a movie which has a main video track and one alternate angle track, plus audio for both english and spanish, in addition to audio for an english commentary track can be conceptualized as shown in the diagram below.
... displaying video text tracks now we'll discuss a slightly more advanced concept that is really useful to know about.

HTML table basics - Learn web development
screenreaders are then able to read out a whole row or column of data at once, which is pretty useful.
...instead of doing this, we can specify the information once, on a <col> element.

Video and Audio APIs - Learn web development
in windbackward() we do the following — bear in mind that when the interval is active, this function is being run once every 200 milliseconds.
...so in effect, we are rewinding the video by 3 seconds, once every 200 milliseconds.

Arrays - Learn web development
in this line we currently have i <= 0, which is a conditional test that causes the for loop to only run once, because it is saying "stop when i is no longer less than or equal to 0", and i starts at 0.
...in an animated scene for example, you might have an array of objects representing the background graphics currently displayed, and you might only want 50 displayed at once, for performance or clutter reasons.

Basic math in JavaScript — numbers and operators - Learn web development
we don't cover these in detail in this article because we wanted to keep it as a simple introduction and only cover the real basic essentials for now; however, once you've read through this module a couple of times it is worth going to the object reference pages and learning more about what's available.
...there is no need to worry about how this works — just concentrate on the math for now.

Object prototypes - Learn web development
note: it is worth reading our more in-depth guide to "using prototypes in javascript", once you've made sense of this section and wish to know more.
... this section is intentionally simplified to make these concepts a little easier to understand when you first meet them.

Test your skills: Object basics - Learn web development
once you've done this, you should then write a string to the variable bandinfo, which will contain a small biography detailing their name, nationality, years active, and style, and the title and release date of their first album.
... the code is not very dry (each bit of code should only be defined once) — you've got the same method defined twice, for example.

CSS performance optimization - Learn web development
previous overview: performance next painting an unstyled page, and then repainting it once styles are parsed would be bad user experience.
...the browser can paint the page once it has downloaded the css and built the css object model.

Multimedia: Images - Learn web development
progressive jpegs, in contrast to normal jpegs, render progressively (hence the name), meaning the user sees a low-resolution version that gains clarity as the image downloads, rather than the image loading at full resolution top-to-bottom or even only rendering once completely downloaded.
... jpeg2000 — once to be successor to jpeg but only supported in safari.

What is web performance? - Learn web development
it is important to minimize the loading and response times, and add additional features to conceal latency by making the experience as available and interactive as possible, as soon as possible, while asynchronously loading in the longer tail parts of the experience.
...this is the process that the browser uses to construct the web document once the files have been downloaded from the server.

Web performance - Learn web development
it would also be helpful to go a bit deeper into these topics, with modules such as: introduction to html css first steps javascript first steps once you've worked through this module, you'll probably be excited to go deeper into web performance — you can find a lot of further teachings in our main mdn web performance section, including overviews of performance apis, testing and analysis tools, and performance bottleneck gotchas.
...once optimized, how can you ensure bloat doesn't come back?

Introduction to the server side - Learn web development
in each case, the code is significantly different: they have different purposes and concerns.
... code running in the browser is known as client-side code and is primarily concerned with improving the appearance and behavior of a rendered web page.

Website security - Learn web development
summary this article has explained the concept of web security and some of the more common threats against which your website should attempt to protect.
...we hope you've enjoyed learning these fundamental concepts, and you're now ready to select a web framework and start programming.

Ember resources and troubleshooting - Learn web development
general troubleshooting, gotchas, and misconceptions this is nowhere near an extensive list, but it is a list of things that came up around the time of writing (latest update, may 2020).
...both of these try to solve the problems of mut by introducing more obvious / "less magic" concepts, avoiding build-time transforms and implicit glimmer vm behavior.

Introduction to client-side frameworks - Learn web development
it follows a similar pattern to the one we used to build a list item element: function builddeletebuttonel(id) { const button = document.createelement('button'); const textcontent = document.createtextnode('delete'); button.setattribute('type', 'button'); button.appendchild(textcontent); return button; } this button doesn't do anything yet, but it will later once we decide to implement our delete feature.
... note: if you want to find out more details about web tooling concepts, have a read of our client-side tooling overview.

Getting started with React - Learn web development
these components can be composed together to create a full ui, and react abstracts away much of the rendering work, leaving you to concentrate on the ui design.
...once you're comfortable with it, however, it will allow you to build user interfaces more quickly and intuitively, and allow others to better understand your codebase at a glance.

Beginning our React todo list - Learn web development
previous overview: client-side javascript frameworks next let's say that we’ve been tasked with creating a proof-of-concept in react – an app that allows users to add, edit, and delete tasks they want to work on, and also mark tasks as complete without deleting them.
...once we have put our styles in place, though, any element with this class will be hidden from sighted users and still available to screen reader users — this is because these words are not needed by sighted users; they are there to provide more information about what the button does for screenreader users that do not have the extra visual context to help them.

TypeScript support in Svelte - Learn web development
once you have typescript configured, you can start using it from a svelte component by just adding a <script lang='ts'> at the beginning of the script section.
... // create the underlying writable store return { subscribe, set: (value: t) => { localstorage.setitem(key, tostring(value)) // save also to local storage as a string return set(value) }, update } } and thanks to generic type inference, typescript already knows that our $todos store should contain an array of todotype: once again, if we wanted to be explicit about it, we could do so in the stores.ts file like this: const initialtodos: todotype[] = [ { id: 1, name: 'visit mdn web docs', completed: true }, { id: 2, name: 'complete the svelte tutorial', completed: false }, ] export const todos = localstore<todotype[]>('mdn-svelte-todo', initialtodos) that will do for our brief tour of typescript generics.

Componentizing our Svelte app - Learn web development
in this article we will concentrate on creating the filterbutton and todo components; we'll get to the others in future articles.
... the code so far git to see the state of the code as it should be at the end of this article, access your copy of our repo like this: cd mdn-svelte-tutorial/05-advanced-concepts or directly download the folder's content: npx degit opensas/mdn-svelte-tutorial/05-advanced-concepts remember to run npm install && npm run dev to start your app in development mode.

Getting started with Svelte - Learn web development
it arguably has fewer concepts and tools to learn than some of the other framework options.
... we encourage you to go through the svelte tutorial for a really quick introduction to the basic concepts, before returning to this tutorial series to learn how to build something slightly more in-depth.

Working with Svelte stores - Learn web development
we'll just leave them as they are, and instead concentrate on persisting our todos.
...make some changes to your app, like pressing the uncheck all button, and check the web storage content once more.

Creating our first Vue component - Learn web development
along the way, we'll learn about a few important concepts such as calling components inside other components, passing data to them via props, and saving data state.
... making components dynamic with props our todoitem component is still not very useful because we can only really include this once on a page (ids need to be unique), and we have no way to set the label text.

Adding a new todo form: Vue events, methods, and models - Learn web development
.once: listens for the event until it's been triggered once, and then no more.
...in the next article, we'll concentrate on fixing this, looking at the different ways vue provides to style components.

Understanding client-side JavaScript frameworks - Learn web development
beginning our react todo list let's say that we’ve been tasked with creating a proof-of-concept in react – an app that allows users to add, edit, and delete tasks they want to work on, and also mark tasks as complete without deleting them.
...along the way, we'll learn about a few important concepts such as calling components inside other components, passing data to them via props and saving data state.

Handling common JavaScript problems - Learn web development
fixing general javascript problems as we said in the previous article on html/css, you should make sure your code is working generally, before going on to concentrate on the cross-browser issues.
...let's fix this problem by running the code once the load event has been fired — remove the console.log() line, and update this code block: let superheroes = request.response; populateheader(superheroes); showheroes(superheroes); to the following: request.onload = function() { let superheroes = request.response; populateheader(superheroes); showheroes(superheroes); } to summarize, anytime something is not working and a value does no...

Setting up your own test automation environment - Learn web development
testing in multiple browsers at once there is also nothing to stop you running the test on multiple browsers simultaneously.
..., method:"put", form:{"status":"passed","reason":"google results showed correct title"}}); } else { console.log('test failed'); request({uri: "https://your-user-name:your-access-key@www.browserstack.com/automate/sessions/" + sessionid + ".json", method:"put", form:{"status":"failed","reason":"google results showed wrong title"}}); } }); }); these are fairly intuitive — once the test completes, we send an api call to browserstack to update the test with a passed or failed status, and a reason for the result.

Client-side tooling overview - Learn web development
this stage of the development process is one that you want the least amount of active interaction with so that once it is configured, it runs mostly automatically, only popping up to say hello if something has gone wrong.
...once all the kinks in the process are flattened out, your tool chain should be something you can forget about and it should just work.

Learn web development
server-side website programming even if you are concentrating on client-side web development, it is still useful to know how servers and server-side code features work.
...we'd like to hear from you about anything you think is wrong or missing on the site, requests for new learning topics, requests for help with items you don't understand, or any other questions or concerns.

Software accessibility: Where are we today?
refreshable braille displays of various sizes a braille embosser audio- and braille- based user interfaces are concepts that software designers are historically untrained for.
... the basic concept is easy - dealing with information when you're blind is like seeing everything through a mail slot - sequentially and methodically.

Index
686 theme concepts theme, add-on themes developed using the webextensions api in firefox enable you to change the look of the browser by adding images to the header area of the firefox browser; this is the area behind the menu bar, toolbars, address bar, search bar, and tab strip.
...once you have defined the colors and image for your theme, the generator will submit your new theme to amo.

Frequently Asked Questions for Lightweight themes
once a theme is installed, it is saved in the add-ons manager, where you can enable or disable them as you wish.
... once a theme is installed, it is saved in the add-ons manager, where you can enable or disable them as you wish.

Browser chrome tests
call finish() once the test is complete.
...if you are adding the first tests in a directory, make sure to also include any head.js you added to support-files, and additionally, ensure that your browser.ini is referenced by a moz.build file somewhere, such as: browser_chrome_manifests += [ 'test/functional/mochitest/browser.ini' ] support-files once added to support-file section of browser.ini support files may be referenced as https://example.com/browser/[path_to_file] or chrome://mochitests/content/browser/[path_to_file].

Creating a spell check dictionary add-on
if you set em:minversion to a lower value, gecko 10-17 will not be able to update your dictionary add-on once the restartless dictionary is installed (bug 782118), and gecko 10-16 may warn the user that your dictionary is not compatible, when users try to update to a newer version of firefox/thunderbird (bug 782115).
... once you have added these files to your zip file and renamed the file to have the .xpi extension, you can install your add-on in firefox and test it.

Debugging Frame Reflow
element size only once and it reports now: block 02d7bcf8 d=1410,300 the block shows the same address as the previous one.
... cell tablecell bccell bctablecell col tablecol colg tablecolgroup tbl table tblo tableouter rowg tablerowgroup row tablerow textctl textinput text text vp viewport once the problem is reduced to a single frame level, placing a breakpoint at displayreflowenterprint in nsframe.cpp is a very efficient way to step through the reflow tree.

HTTP logging
once you've reproduced the problem, exit firefox and look for the generated log files in your temporary directory.
... once you've reproduced the problem, exit firefox and look for the generated log files in your temporary directory.

Inner and outer windows
this article will try to explain the concepts of inner and outer windows.
...then add to that the concept of frames, whereby a document in a window can itself contain other documents, which in turn can contain more documents.

mach
registering mach command providers once you've written a python module providing a mach command, you'll need to register it with mach.
... submitting a mach command for approval once you've authored a mach command, submit the patch for approval.

Frame script loading and lifetime
e script var mm = gbrowser.selectedbrowser.messagemanager; mm.loadframescript('data:,dump("foo\\n")', true); loadframescript() takes two mandatory parameters: a url that points to the frame script you want to load a boolean flag, allowdelayedload note: if the message manager is a global frame message manager or a window message manager, loadframescript() may load the script multiple times, once in each applicable frame.
...so once you load them, they will stay loaded until the tab is closed, even if you reload the document or navigate.

Embedding the editor
we need a concept of an "editing session" - a single top-level document which is editable, and which may embody more than one editor.
...in composer, we can pose these dialogs from js (once some nsifile problems have been solved).

Gecko SDK
once the sdk enters beta, it is suitable for building extensions; your component should work with release builds of the sdk without any modifications.
... once that's done, you should perform the following command: ln -s /opt/local/lib/libintl.8.dylib /opt/local/lib/libintl.3.dylib this should fix the problem.

Getting Started with Chat
general rules and etiquette once you have your client set up (see software below) and are connected, there are some basic rules you should follow to ensure the most enjoyable and productive experience: as with all mozilla forums and events, agreeing to our community participation guidelines is a requirement for participation.
... /msg nickserv identify password once registered, you need to type this every time you want to sign into channels using your registered nickname /msg nickserv help this displays a list of commands which can be used with nickserv /msg nickserv help register this displays helpful information about nickname registration /msg nickserv help identify this displays helpful information about identifying yo...

Internationalized Domain Names (IDN) Support in Mozilla Browsers
don't forget to set the value of these preferences to "default" once you are finished with testing!
...of particular concern for japanese users is the one in which full-width japanese roman characters are not normalized to ascii roman characters.

AddonManager
the callbacks will be called just once but that may be before or after the method returns.
... note: calling this method more than once for the same add-on will replace the last change that was recorded with the new one; an add-on can only appear once across all change types.

CustomizableUI.jsm
callers should ensure that no matter what happens they call endbatchupdate once for each call to beginbatchupdate, even if there are exceptions in the code in the batch update.
...however, once the user reopens a window, the widget will move back to its 'proper' area automagically.

PopupNotifications.jsm
to use this, you first need to import the code module into your javascript scope: components.utils.import("resource://gre/modules/popupnotifications.jsm"); once you've imported the module, you can then use the popupnotifications object it exports; this object provides methods for creating and displaying popup notification panels.
...any combination of the following properties may be provided: persistence an integer value indicating the number of page loads for which the notification will persist; once this many page loads have occurred, the notification may dismiss automatically.

Using JavaScript code modules
javascript code modules are a concept introduced in gecko 1.9 and can be used for sharing code between different privileged scopes.
...once this method has been called, references to the module will continue to work but any subsequent import of the module will reload it and give a new reference.

WebRequest.jsm
onheadersreceived triggered once response headers have been received.
... onresponsestarted triggered once the browser has started to receive the response body.

XPCOMUtils.jsm
definelazygetter takes three arguments: the object to define the property on the name of the property defined the getter function itself, which returns the value and which will be called just once, the first time code tries to access the property.
...this function is called exactly once.

L10n testing with xcode
setting up your l10n testing environment once you have your l10n testing environment set up in xcode, testing your firefox on ios localization is a breeze.
... launching & testing your firefox on ios localization the ios simulator is fairly easy to use once you launch your app.

Localization content best practices
'do you want to save the text?' suffixes in basque: where english tends to use expressions such as 'to the' or 'from the', basque adds an ending to a word to express the same concept.
...these are generally not complete sentences, but instead, phrases that convey the idea of a concept or action.

Localizing with Mozilla Translator
the first thing to do, once you have your mercurial local repository up and working, is create a new product...
... if you have opted for the first solution, you will find yourself with some new products completely untranslated (once you update each of them).

QA phase
if you don't have a lot of experience with code, you might even be concerned that you've broken something (oops!).
... enter the following command to perform the configuration: $ ./mach configure once your command-line finishes spitting out the config command's output, navigate to the newly created directory: $ cd ../firefox-build/browser/locales now you're ready to build!

Creating localizable web applications
bad: require_once('lib/user.php'); $user = new personauser(); snippet 2.
... good: require_once('templates/footer.php'); if it's not possible to remove the app logic code, you should consider using gettext.

Mozilla Style System
for css style sheets, they correspond to css's concept of rules.
...the style context has a getter for each struct, and nsiframe, which represents the concept of a css box (or rendering object), also has getters that forward to the frame's style context.

Gecko Profiler FAQ
it is quite reasonable to actually run the browser for 40 minutes and once the said leaks have happened capture the profiles and study what went wrong.
... [jesup] ok, that's the equivalent to itimer_real, kinda, except that per the previous question it doesn't interrupt every thread at once and snapshot the thread you started the itimer on, it interrupts each thread one at a time, which likely means distortion of the measurement if the number of threads monitored is significant (especially at high sample rates).

Power profiling overview
basic physics concepts in physics, power is the rate of doing work.
... although power is an instantaneous concept, in practice measurements of it are determined in a non-instantaneous fashion, i.e.

Phishing: a short definition
web authentication supports millions of readily avilable fido u2f usb security keys, and will support the more advanced fido 2.0 keys, once made available.
...after verifying username and password, the user is prompted to open the otp app and enter the corresponding 6-digit code, representing a hashed version of the secret key and a nonce - potentially time-based.

Nonblocking IO In NSPR
once associated with an i/o completion port, we can't disassociate the socket from the i/o completion port.
...once the io mode of a socket is committed, it cannot be changed.

HTTP delegation
once nss is finished providing all details, it will request to initiate the actual network communication (sec_httprequest_trysendandreceivefcn).
...once the http response has been obtained from the http server, the function will provide the results in its "out parameters".