Firefox Release

December 1, 2014

Version 34.0.5, first offered to Release channel users on December 1, 2014

We'd also like to extend a special thank you to all of the new Mozillians who contributed to this release of Firefox!


  • Default search engine changed to Yahoo! for North America

  • Default search engine changed to Yandex for Belarusian, Kazakh, and Russian locales

  • Improved search bar (en-US only)

  • Firefox Hello real-time communication client

  • Easily switch themes/personas directly in the Customizing mode

  • Wikipedia search now uses HTTPS for secure searching (en-US only)

  • Recover from a locked Firefox process in the "Firefox is already running" dialog on Windows


  • Various security fixes

  • CSS transitions start correctly when started at the same time as changes to display, position, overflow, and similar properties

  • Fullscreen video on Mac disables display sleep, and dimming, during playback

  • Various Yosemite visual fixes (see bug 1040250)


  • Disabled SSLv3

  • Proprietary window.crypto properties/functions re-enabled (to be removed in Firefox 35)

  • Firefox signed by Apple OS X version 2 signature


  • Developer Information
  • WebIDE: Create, edit, and test a new Web application from your browser

  • Highlight all nodes that match a given selector in the Style Editor and the Inspector's Rules panel

  • Improved User Interface of the Profiler

  • console.table function added to web console

Web Platform

  • ECMAScript 6 WeakSet Implemented

  • JavaScript Template Strings Implemented

  • CSS3 Font variants and features control (e.g. kerning) implemented

  • WebCrypto: RSA-OAEP, PBKDF2 and AES-KW support

  • WebCrypto: wrapKey and unwrapKey implemented

  • WebCrypto: Import/export of JWK-formatted keys

  • matches() DOM API implemented (formerly mozMatchesSelector())

  • Performance.now() for workers implemented

  • WebCrypto: ECDH support

All Firefox downloads