An Interview With Douglas Bowman of Wired News - Archive of obsolete content
as i was designing the product, i began discovering a broader set of web standards, and was quickly swayed by the advantages i could see if we were to adopt them.
...around that time, i started discovering great sites like glish.com and bluerobot.com.

Index - Firefox Developer Tools
56 css flexbox inspector: examine flexbox layouts guide, inspector, tools, flexbox the flexbox inspector allows you to examine css flexbox layouts using the firefox devtools, which is useful for discovering flex containers on a page, examining and modifying them, debugging layout issues, and more.
... 57 css grid inspector: examine grid layouts guide, inspector, tools the grid inspector allows you to examine css grid layouts using the firefox devtools, discovering grids present on a page, examining and modifying them, debugging layout issues, and more.

CSS Flexbox Inspector: Examine Flexbox layouts - Firefox Developer Tools
the flexbox inspector allows you to examine css flexbox layouts using the firefox devtools, which is useful for discovering flex containers on a page, examining and modifying them, debugging layout issues, and more.
... discovering flex containers when an html element on your page has display: flex applied to it, a number of features are made available in the devtools to provide easy access to flexbox layout features.

CSS Grid Inspector: Examine grid layouts - Firefox Developer Tools
the grid inspector allows you to examine css grid layouts using the firefox devtools, discovering grids present on a page, examining and modifying them, debugging layout issues, and more.
... discovering css grids when an html element on your page has display: grid applied to it, a number of features are made available in the devtools to provide easy access to grid features.

Miscellaneous - Archive of obsolete content
see also http://mxr.mozilla.org/seamonkey/source/browser/base/content/browser.js#4674 discovering which element in the loaded document has focus // focusedcontrol stores the focused field, or null if there is none.

Index - Archive of obsolete content
2080 browser feature detection compatibility, cross-browser_development, dom, gecko, obsolete, web development an experimental approach to discovering degree of support for standards.

Browser Feature Detection - Archive of obsolete content
an experimental approach to discovering degree of support for standards.

Archived open Web documentation - Archive of obsolete content
browser feature detection an experimental approach to discovering degree of support for standards css obsolete css features displaying notifications (deprecated) firefox offers support for "desktop notifications"; these are notifications that are displayed to the user outside the context of the web content, using the standard notification system provided by the operating system.

mach
if you don't use mach, you have to find another solution for the following problems: discovering what commands or make targets are available (mach exposes everything through mach help while inside "mozilla-central" , else you'll just get a cryptic error message) making more sense out of command output (mach offers terminal colorization and structured logging) getting productive tools in the hands of others (mach "advertises" tools to people through mach help (unless it actually just gives ...

NSS 3.14 release notes
applications may use this callback to inform libpkix whether or not candidate certificate chains meet application-specific security policies, allowing libpkix to continue discovering certificate paths until it can find a chain that satisfies the policies.

nsIChannel
load_retargeted_document_uri 17 if the end consumer for this load has been retargeted after discovering its content, this flag will be set: load_replace 18 this flag is set to indicate that this channel is replacing another channel.

Index - Web APIs
2684 navigatorplugins api, experimental, html dom, interface, mixin, navigator, navigatorplugins, plugins, reference the navigatorplugins mixin adds to the navigator interface methods and properties for discovering and interacting with plugins installed into the browser.

NavigatorPlugins - Web APIs
the navigatorplugins mixin adds to the navigator interface methods and properties for discovering and interacting with plugins installed into the browser.

OpenType font features guide - CSS: Cascading Style Sheets
discovering availability of features in fonts this is sometimes the trickiest thing to work out if you don't have any documentation that came with the fonts (many type designers and foundries will provide sample pages and css just for this very reason).