Firefox 44 for developers

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Firefox 44, based on Gecko 44, will ship in January 2016. This article provides information about the changes in this release that will affect developers. Nightly builds of what will become Firefox 44 are currently available on the Beta channel.

Изменения, для Веб разработчиков

Инструменты разработчика

• Added keyboard shortcut S to scroll the selected node into view in the HTML pane of the Page Inspector (ошибка 1203147).

HTML

• <link rel="prefetch"> now obeys the crossorigin attribute (ошибка 1214819).

CSS

• position: fixed; now always creates a new stacking context (ошибка 1179288).
• The support of unicode-range has been enabled by default (ошибка 1119062).
• Our experimental implementation of CSS Writing Modes has been updated to reflect the latest specification:
  • The value sideways of the text-orientation property has been implemented and sideways-right has been made an alias of it (ошибка 1193488).
  • The value sideways-rl and sideways-lr of the writing-mode property (ошибка 1193488 and ошибка 1193519).
• The non-standard properties -moz-math-display and -moz-window-shadow are no more available from Web content (ошибка 1207002, ошибка 1211040, and ошибка 1212607).
• The font-style property now distinguishes between oblique and italic when both variants are available (ошибка 543715).
• Though not supported, the properties marks, orphans, page, size, and widows, were parsed and @supports was incorrectly reporting them as supported; this has been fixed and the properties are not parsed anymore, nor marked as supported (ошибка 1215702).
• The internal value -moz-mac-unified-toolbar has been removed from the possible values for the -moz-appearance property (ошибка 1206468).
• The font-style property now makes the distinction between oblique and italic: if both faces are present the correct one is now selected (ошибка 543715).

JavaScript

New APIs

• Symbol.toPrimitive, Symbol.prototype[@@toPrimitive], and Date.prototype[@@toPrimitive] have been implemented (ошибка 1054756).

Changes

• The let and const bindings in the global level have been made compliant with ES2015 semantics. See ошибка 589199 and the blog post "Breaking changes in let and const in Firefox Nightly 44". In addition, let is now available to default Web JavaScript (strict and non-strict) and does not require a version opt-in anymore (ошибка 932517).
• If typed arrays' (like Int8Array) and ArrayBuffer) constructors are called as a function without the new operator, a TypeError is now thrown as per the ES6 specification (ошибка 980945, ошибка 1214936).
• The RegExp sticky flag now follows the ES2015 standard for anchored sticky regular expressions (ошибка 773687).
• The JavaScript shell (SpiderMonkey's REPL) now defaults to the default, Web-compatible JS version (and not JS1.7+ anymore) (ошибка 1192329).

Removals

• Support for the non-standard let blocks has been dropped (ошибка 1167029.
• The non-standard and deprecated property Object.prototype.__noSuchMethod__ has been removed (ошибка 683218).

Interfaces/APIs/DOM

DOM & HTML DOM

• For compatibility with specific existing sites, the property Document.charset has been implemented as an alias of Document.characterSet (ошибка 647621).
• Support for the window.sidebar.addSearchEngine() method, which allowed Web pages to invoke an installation of a Sherlock plugin, has been dropped and now it just logs a warning in the Web Console (ошибка 862148).
• To fight unwanted pop-ups, prompts requested in Window.onbeforeunload of pages that have not been interacted with are no more displayed (ошибка 636905).
• The deprecated method MessageEvent.initMessageEvent() has been reimplemented for backward compatibility (ошибка 949376).
• The obsolete DocumentType.internalSubset has been removed (ошибка 801545).
• For compatibility with existing sites, the properties Window.orientation, Window.onorientationchange, as well as the orientationchange event have been implemented (ошибка 920734).
• Iframe with explicit fullscreen request should not exit fullscreen implicitly (ошибка 1187801).
• The events mouseover, mouseout, mouseenter, mouseleave, pointermove, pointerover, pointerout, pointerenter and pointerleave are now triggered for disabled form elements (ошибка 218093).
• The method Element.webkitMatchesSelector() has been added (ошибка 1216193).

• To match the spec, the method Document.createAttribute() now lowercases the input (ошибка 1176313).

WebGL

• Uniform Buffer Objects have been implemented (ошибка 1048747).

IndexedDB

• The IDBIndex.getAll() and IDBIndex.getAllKeys() are now available by default (ошибка 1196841).

Service Workers

• The ServiceWorkerMessageEvent and ExtendableMessageEvent interfaces have been implemented (ошибка 1143717 and ошибка 1207068).
• Headers objects now support a pair iterator, meaning that the methods Headers.entries(), Headers.keys(), and Headers.values() are now available; Symbol.iterator now also returns the default iterator for them (ошибка 1108181).
• The XMLHttpRequest API has been disabled on Service Workers (ошибка 931243).
• The interface FetchEvent now extends ExtendableEvent, giving it access to the ExtendableEvent.waitUntil() method. (ошибка 1214772).
• Following a recent change in the specification, FetchEvent.client has been removed (ошибка 1218135).
• To match the latest specification, the ServiceWorkerContainer.onreloadpage has been removed (ошибка 1218139).
• The event handlers ServiceWorkerGlobalScope.onbeforeevicted and ServiceWorkerGlobalScope.onevicted have been removed as they weren't following the spec. They will be reintroduced in the future, but their removal will allow feature detection to work as expected (ошибка 1218142).
• In the FetchEvent() constructor, if the isReload member is not present in the options dictionary, it now defaults to false (ошибка 1216401).
• The Client.frameType property is now implemented on the right interface; it was on WindowClient before (ошибка 1218146).
• When AppCache is used to provide offline support for a page, a warning message is now displayed in the console advising developers to use Service workers instead (ошибка 1204581.)
• Service workers have been enabled by default in Gecko.

WebRTC

• WebRTC interfaces have been unprefixed (ошибка 1155923). In particular:
  • mozRTCPeerConnection is now RTCPeerConnection.
  • mozRTCIceCandidate is now RTCIceCandidate.
  • mozRTCSessionDescription is now RTCSessionDescription.
• The RTCDataChannel.bufferedAmountLowThreshold and RTCDataChannel.onbufferedamountlow properties, as well as the bufferedamountlow event, have been implemented (ошибка 1178091).
• The attribute RTCPeerConnection.canTrickleIceCandidates has been added, the non-standard method RTCPeerConnection.updateIce() removed (ошибка 1209744).
• The MediaStream interface now supports the MediaStream.addTrack() and MediaStream.removeTrack() methods (ошибка 1103188).
• The constructor MediaStream() has been implemented (ошибка 1070216).

New APIs

• An experimental implementation of the Canvas API in Workers has landed: OfflineCanvas and HTMLCanvasElement.transferControlToOffscreen() are available behind the gfx.offscreencanvas.enabled preference, currently disabled by default (ошибка 709490).
• The Text2Speech API, part of Web Speech API, has now an OS X backend. But this is disabled by default (ошибка 1003452).

Miscellaneous

• URLSearchParams objects now support a pair iterator, meaning that the methods URLSearchParams.entries(), URLSearchParams.keys(), and URLSearchParams.values() are now available; Symbol.iterator now also returns the default iterator for them (ошибка 1085284).
• FormData objects now support a pair iterator, meaning that the methods FormData.entries(), FormData.keys, and FormData.values() are now available; Symbol.iterator now also returns the default iterator for them (ошибка 1127703).
• When XMLHttpRequest.send() is used with an HTML document, it now uses text/html instead of application/xml (ошибка 918771).
• Speech synthesis (text-to-speech) has been implemented in Firefox Desktop for Mac and Linux, hidden behind the media.webspeech.synth.enabled flag in about:config (ошибка 1003452, ошибка 1003464.) See Web Speech API for more information.
• Elements inside a <frame> or an <object> can't be set full-screen anymore (ошибка 1212299).

MathML

No change.

SVG

No change.

Audio/Video

No change.

HTTP

• Support for the Brotli algorithm has been added and both Accept-Encoding and Content-Encoding headers now support the br value (ошибка 366559 and ошибка 1211916).
• Incorrect support of HTTP/2 headers containing line breaks ('/n') have been removed as the spec doesn't allow it, unlike HTTP/1 (ошибка 1197847).

Networking

No change.

Security

• RC4 is now also disabled by default on Beta and Release versions of the browser (ошибка 1201025).

Changes for add-on and Mozilla developers

Interfaces

No change

XUL

No change.

JavaScript code modules

• Added LIKE support to Sqlite.jsm (ошибка 1188760).
• Added Snackbars.jsm module to Firefox for Android (ошибка 1215026)

XPCOM

No change.

Other

No change.

See also

• Site compatibility for Firefox 44

Older versions