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Firefox Developer Edition
Release Notes

Release Notes tell you what’s new in Firefox. As always, we welcome your feedback. You can also file a bug in Bugzilla or see the system requirements of this release.

36.0a2
Firefox Developer Edition

December 5, 2014

Version 36.0a2, first offered to Firefox Developer Edition channel users on December 5, 2014

For more information about Developer Edition please see this MDN article and also this hacks.mozilla.org post.

New

  • Pinned tiles on the new tab page can be synced

  • Support for the full HTTP/2 protocol. HTTP/2 enables a faster, more scalable, and more responsive web.

Fixed

Changed

  • -remote option removed

  • No longer accept insecure RC4 ciphers whenever possible

  • Shut down hangs will now show the crash reporter before exiting the program

Developer

Web Platform

  • Implemented a subset of the Media Source Extensions (MSE) API to allow native HTML5 playback on YouTube (Windows Vista or later only)

  • Support for the ECMAScript 6 Symbol data type added

  • WebSocket now available in Web Workers

  • CSSOM-View scroll behavior implemented allowing smooth scrolling of content without custom libraries

  • object-fit and object-position implemented.
    Defines how and where the content of a replaced element is displayed

  • isolation CSS property implemented.
    Create a new stacking context to isolate groups of boxes to control which blend together

  • CSS3 will-change property implemented.
    Hints the browser of elements that will be modified. The browser will
    perform some performance optimization for these

  • Improved ES6 generators for better performance

  • Changed JavaScript 'const' semantics to conform better to the ES6 specification.
    The const declaration is now block-scoped and requires an initializer. It also can not be redeclared anymore.

  • <meta name="referrer"> implemented for more privacy. Allows to control the content of the HTTP referer header.

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