See what’s new in Firefox!

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.


Firefox Beta

June 8, 2016

Version 48.0beta, first offered to Beta channel users on June 8, 2016


  • Process separation (e10s) is enabled for some of you. Like it? Let us know and we'll roll it out to more

  • Roar for moar protection against harmful downloads! We've got your back

  • Add-ons that have not been verified and signed by Mozilla will not load

  • GNU/Linux fans: Get better Canvas performance with speedy Skia support. Try saying that three times fast

  • Windows folks: Tab (move buttons) and Shift+F10 (pop-up menus) now behave as they should in Firefox customization mode

  • Searching for something already in your bookmarks or open tabs? We added super smart icons to let you know

  • WebRTC embetterments:

    • Delay-agnostic AEC enabled
    • Full duplex for GNU/Linux enabled
    • ICE Restart & Update is supported
    • Cloning of MediaStream and MediaStreamTrack is now supported
  • Windows 7 systems without Platform Update can now use D3D11 WARP

  • The media parser has been redeveloped using the Rust programming language


  • Improved step debugging on last line of functions

  • Heyo, Jabra & Logitech C920 webcam users. We fixed those pesky WebRTC bugs causing frequency distortions. Buh-bye, squeaky voice!


  • Au revoir to Windows Remote Access Service modem Autodial

  • So long to support for 10.6, 10.7 and 10.8. Now we can focus on where most Mac users are: 10.9. Don't forget to upgrade!

  • After version 48, SSE2 CPU extensions are going to be required on Windows


  • Workers can now use the Web Crypto API

  • Expand network requests from the console panel to view request details in line, so you can see things in context

  • This theme is hot, hot, hot! Say hi to the Firebug theme for Developer Tools

  • Add-on development just got easier because you can reload them from about:debugging — because we're all about debugging

  • Old and busted: Error Console. New hotness: Browser Console for your debugging pleasure

  • Content Security Policy (CSP) is now enforced for WebExtensions. (Who's down with CSP?)

  • We're putting the spotlight on the background. Now you can debug WebExtensions background content scripts and background pages

  • The memory tool now has a tree map view for your debugging pleasure. It's a little bit of "boo" and a whole lot of "ya"

  • Want to move absolute & fixed positioned elements? (Who doesn't, right?) Now you can with our geometry editor.

  • WebExtensions support is now considered as stable

Developer Information


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