Mozilla announced Firefox 28 release today. As soon as we heard the news we rushed to add this browser to our cross-browser testing platform. We just finished installing Firefox 28 to Browserling and you can already cross-browser test your sites in this browser version.

Browser testing in Firefox 28

Try Firefox 28 in Browserling now!

Firefox 28 Key New Features and Updates

  • Now that spdy/3 is implemented support for spdy/2 has been removed and servers without spdy/3 will negotiate to http/1 without any penalty.
  • Mac OS X: Notification Center support for web notifications.
  • Horizontal HTML5 audio/video volume control.
  • VP9 video decoding implemented.
  • Support for Opus in WebM.

Firefox 28 Web Developers Updates

  • Support for MathML 2.0 'mathvariant' attribute.
  • Background thread hang reporting.
  • Support for multi-line flexbox in layout.
  • The console.exception property has been added.
  • The console.assert property has been added.
  • App Manager: a new Manifest Editor was added.
  • App Manager: the toolbox used for debugging apps is now embedded in the app manager UI.
  • Web Console: added a "split console" mode - press Escape to quickly open the console in any other tool.
  • Web Console: added a dark theme for the output.
  • Debugger: pretty-print minified JavaScript.
  • Debugger: simply hover over any variable or click on it to bring up a pop-up that displays the current value.
  • Inspector: added a color picker in rules view and various tooltips.
  • Browser Toolbox: allows add-on and platform developers to use almost all of the developer tools while targeting the browser itself.
  • Support for multi-line flexbox has been added.
  • Longhand East Asian counter styles have been implemented.
  • Experimental support for the background-blend-mode property has been added, but is disabled by default.
  • The none value has been added to font-variant-ligatures.
  • Support for the :hover user action pseudo-class on pseudo-elements has been implemented.
  • <input type=color> and <input type=number> have been implemented but are disabled by default.
  • New Array methods have been implemented: Array.prototype.entries() and Array.prototype.keys().
  • HTMLVideoElement.canPlayType('video/webm') now reports maybe.
  • The File constructor, e.g. new File(["foo"], "foo.txt") has been implemented.
  • The two attributes Window.screenX and Window.screenY now return CSS pixels.
  • Support of the mathvariant attribute in MathML has been added.

Firefox 28 Security Updates

  • Out-of-bounds write through TypedArrayObject after neutering.
  • Out-of-bounds read/write through neutering ArrayBuffer objects.
  • Use-after-free in TypeObject.
  • Privilege escalation using WebIDL-implemented APIs.
  • SVG filters information disclosure through feDisplacementMap.
  • Memory corruption in Cairo during PDF font rendering.
  • Information disclosure through polygon rendering in MathML.
  • Android Crash Reporter open to manipulation.
  • Content Security Policy for data: documents not preserved by session restore.
  • WebGL content injection from one domain to rendering in another.
  • Local file access via Open Link in new tab.
  • onbeforeunload and Javascript navigation DOS.
  • Spoofing attack on WebRTC permission prompt.
  • crypto.generateCRMFRequest does not validate type of key.
  • Out of bounds read during WAV file decoding.
  • Files extracted during updates are not always read only.
  • Miscellaneous memory safety hazards.

Firefox 28 Unresolved Issues

  • Text Rendering Issues on Windows 7 with Platform Update KB2670838 (MSIE 10 Prerequisite) or on Windows 8.1 has a workaround.
  • Echo cancellation on fails.

Happy cross-browser testing in Firefox 28!