The Publicity Stream API
possible error codes include: denied - if the user refuses to publicize the activity permissiondenied - if the publicizing site is not allowed to post to the publicity stream networkerror - if the publicity server is unreachable activityparseerror - if the activity contains syntax errors (not proper json) invalidactivity - if the activity contains semantic errors (i.e.
...possible error codes include: denied - if the user does not log in correctly permissiondenied - if the site is not allowed to access the publicity stream networkerror - if the publicity server is unreachable for_apps is a json list of apps that this store has (each represented as its origin url), so that stream events not relating to applications in a given presentation context can be excluded from the return value.

Source map errors - Firefox Developer Tools
the message looks a little different in this case: in this case, the error will also be displayed in the source tab in the debugger: networkerror when attempting to fetch resource a bug in firefox prevents it from loading source maps for web extensions.
... source-map-fehler: typeerror: networkerror when attempting to fetch resource.

FontFace.load - Web APIs
return value a promise that resolves with a reference to the current fontface object when the font loads or rejects with a networkerror if the loading process fails.
... exceptions networkerror indicates that the attempt to load the font failed.

DOMError - Web APIs
networkerror a network error occurred.

DOMException - Web APIs
(legacy code value: 18 and legacy constant name: security_err) networkerror a network error occurred.

FetchEvent.respondWith() - Web APIs
exceptions exception notes networkerror a network error is triggered on certain combinations of fetchevent.request.mode and response.type values, as hinted at in the "global rules" listed above.

NDEFWriter.write() - Web APIs
networkerror transfer failed after it already started (e.g., the tag was removed from the reader).

RTCDataChannel.close() - Web APIs
if the transport was closed with an error, the rtcdatachannel is sent a networkerror event.

RTCDataChannel.send() - Web APIs
networkerror the specified data would need to be buffered, and there isn't room for it in the buffer.

SharedWorker() - Web APIs
a networkerror is raised if the mime type of the worker script is incorrect.

Worker() - Web APIs
a networkerror is raised if the mime type of the worker script is incorrect.

WorkerGlobalScope.importScripts() - Web APIs
exceptions networkerror imported scripts were not served with a valid javascript mime type (i.e.

How to check the security state of an XMLHTTPRequest over SSL - Web APIs
0e: // ns_error_net_timeout, network(14) errname = 'networktimeouterror'; break; // hostname lookup failed case 0x804b001e: // ns_error_unknown_host, network(30) errname = 'domainnotfounderror'; break; case 0x804b0047: // ns_error_net_interrupt, network(71) errname = 'networkinterrupterror'; break; default: errname = 'networkerror'; break; } } // xxx we have no tcperror implementation right now because it's really hard to // do on b2g18.

XMLHttpRequest.send() - Web APIs
networkerror the resource type to be fetched is a blob, and the method is not get.