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Firefox 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.

42.0 Firefox Release

November 3, 2015

Version 42.0, first offered to Release channel users on November 3, 2015

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

New

  • Private Browsing with Tracking Protection blocks certain Web elements that could be used to record your behavior across sites

  • Control Center that contains site security and privacy controls

  • Indicator added to tabs that play audio with one-click muting

  • Login Manager improvements:

    • Improved heuristics to save usernames and passwords
    • Edit and show all logins in line, Copy/Paste usernames/passwords from the Context menu
    • Migration imports your passwords to Firefox from Google Chrome for Windows and Internet Explorer; import anytime from the Login Manager
  • WebRTC improvements:

    • IPV6 support
    • Preferences for controlling ICE candidate generation and IP exposure
    • Hooks for extensions to allow/deny createOffer/Answer
    • Improved ability for applications to monitor and control which devices are used in getUserMedia

Fixed

Changed

  • Improved performance on interactive websites that trigger a lot of restyles

Developer

Web Platform

Unresolved

  • URLs containing a Unicode-format Internationalized Domain Name (IDN) are not redirected properly, leading to a Server Not Found error.

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