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63.0beta

Firefox Beta

September 5, 2018

Version 63.0beta, first offered to Beta channel users on September 5, 2018

New

  • On macOS, WebGL power preferences allow non-performance-critical applications and applets to request the low-power GPU instead of the high-power GPU in multi-GPU systems

  • Improved Windows 10 integration: your Firefox theme now matches your OS Dark / Light mode

  • WebExtensions now run in their own process on Linux

  • Faster tab switching in the majority of cases for our macOS users

  • Improved the reactivity of Firefox on macOS

Changed

  • In the Library, the Open in Sidebar feature for individual bookmarks was removed

  • Never check for updates option removed from about:preferences. If a substitute is needed, we recommend using the DisableAppUpdate enterprise policy

  • Firefox now warns about having multiple windows/tabs open when quitting from the main menu.

  • The Ctrl+Tab shortcut now displays thumbnail previews of your tabs and cycles through tabs in recently used order. This new default behavior is activated only in new profiles and can be changed in your preferences

  • The build infrastructure of Firefox on Windows moved to the Clang tool chain, bringing important performance gains

Developer

Developer Information