Today Firefox 44 was released and we just installed it to our browser cloud. You can already start cross-browser testing your websites in this new browser version!

Cross-browser testing in Firefox 44

Try Firefox 44 in Browserling now!

What's new in Firefox 44

  • Enable WebM/VP9 video support on systems that don't support MP4/H.264.
  • Improved warning pages for certificate errors and untrusted connections.
  • Support the brotli compression format via HTTPS content-encoding.
  • Enable H.264 if system decoder is available.
  • Firefox can now get Push Notifications from your favorite sites.
  • Screenshot commands allow user choice of pixel ratio in Developer Tools.
  • In the animation-inspector timeline, lightning bolt icon next to animations running on the compositor thread.

What's changed in Firefox 44

  • Support for Direct2D 1.0 has been dropped. Windows 7 users can install the Platform Update to re-enable Direct2D support (to fix font rendering issues).
  • To support unicode-range descriptor for webfonts, font matching under Linux now uses the same font matching code as other platforms.
  • Firefox will no longer trust the Equifax Secure Certificate Authority 1024-bit root certificate or the UTN - DATACorp SGC to validate secure website certificates.
  • On-screen keyboard support temporarily turned off for Windows 8 and Windows 8.1.
  • Use a SHA-256 signing certificate for Windows builds, to meet new signing requirements.
  • Firefox has removed support for the RC4 cipher.
  • Stricter validation of web fonts.

What's fixed in Firefox 44

  • Windows XP and Vista screensaver doesn't disable when watching videos.
  • Various security fixes.

Security updates and fixes in Firefox 44

  • Addressbar spoofing through stored data url shortcuts on Firefox for Android.
  • Firefox allows for control characters to be set in cookie names.
  • Errors in mp_div and mp_exptmod cryptographic functions in NSS.
  • Delay following click events in file download dialog too short on OS X.
  • Addressbar spoofing attacks.
  • Use-after-free in NSS during SSL connections in low memory.
  • RC4 is now also disabled by default on Beta and Release versions of the browser and the whitelist is now empty by default.
  • Unsafe memory manipulation found through code inspection.
  • Buffer overflow in WebGL after out of memory allocation.
  • Missing delay following user click events in protocol handler dialog.
  • Lightweight themes on Firefox for Android do not verify a secure connection.
  • Application Reputation service disabled in Firefox 43.
  • Miscellaneous memory safety hazards.
  • Out of Memory crash when parsing GIF format images.

Developer updates and fixes in Firefox 44

  • Right click on a logged object in the console to store it as a global variable on the page.
  • Service Workers API.
  • Visual tools for Layout and Styles: Display rulers along the viewport to verify size and position and use the measurement tool to easily detect spacing and alignment problems. Use CSS filters to preview and create real-time effects like drop-shadows, sepia, etc.
  • Built-in JSON reader to intuitively view, search, copy and save data without extensions.
  • Jump to function definitions in the debugger with Cmd-Click.
  • Visual tools for Animation: View/Edit CSS animation keyframe rules directly in the inspector. Visually modify the cubic-bezier curve that drives the way animations progress through time. Discover and scrub through all CSS animations and transitions playing on the page.
  • The rule view now displays styles using their authored text, and edits in the rule view are now linked to the style editor.
  • WebSocket Debugging API and add-on.
  • New memory tool for inspecting the memory heap.

HTML, CSS, Javascript updates in Firefox 44

  • <link rel="prefetch"> now obeys the crossorigin attribute.
  • position: fixed; now always creates a new stacking context.
  • Support of unicode-range has been enabled by default.
  • The value sideways of the text-orientation property has been implemented and sideways-right has been made an alias of it.
  • The value sideways-rl and sideways-lr of the writing-mode property.
  • The font-style property now distinguishes between oblique and italic when both variants are available.
  • Symbol.toPrimitive, Symbol.prototype[@@toPrimitive], and Date.prototype[@@toPrimitive] have been implemented.
  • The let and const bindings in the global level have been made compliant with ES2015 semantics.
  • If typed arrays' (like Int8Array) and ArrayBuffer) constructors are called as a function without the new operator.
  • Support for the non-standard let blocks has been dropped.
  • The non-standard and deprecated property Object.prototype.__noSuchMethod__ has been removed.

DOM updates in Firefox 44

  • For compatibility with specific existing sites, the property Document.charset has been implemented as an alias of Document.characterSet.
  • 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.
  • The obsolete property DocumentType.internalSubset has been removed.
  • The events mouseover, mouseout, mouseenter, mouseleave, pointermove, pointerover, pointerout, pointerenter and pointerleave are now triggered for disabled form elements.
  • To match the spec, the method Document.createAttribute() now converts the input to lower case.

Canvas and WebGL updates in Firefox 44

  • A new experimental OffscreenCanvas API that allows rendering contexts (such as WebGL) to run in Web Workers has been implemented.
  • Uniform Buffer Objects in WebGL have been implemented.

IndexedDB updates in Firefox 44

  • The IDBIndex.getAll() and IDBIndex.getAllKeys(), and there counterparts on IDBObjectStore are now available by default.

HTTP protocol updates in Firefox 44

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

Service workers updates in Firefox 44

  • The ServiceWorkerMessageEvent and ExtendableMessageEvent interfaces have been implemented.
  • The XMLHttpRequest API has been disabled on Service Workers.
  • To match the latest specification, the ServiceWorkerContainer.onreloadpage has been removed.
  • The Client.frameType property is now implemented on the right interface; it was on WindowClient before.
  • Service workers have been enabled by default in Gecko.

WebRTC updates in Firefox 44

  • WebRTC interfaces have been unprefixed. 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.
  • The constructor MediaStream() has been implemented.

Unresolved issues in Firefox 44

  • Trusteer Rapport is severely impacting the stability of Firefox.

Happy cross-browser testing in Firefox 44!