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

March 7, 2017

Version 53.0beta, first offered to Beta channel users on March 7, 2017


  • Lightweight themes are now applied in private browsing windows

  • Reader Mode now displays estimated reading time for the page

  • Two new 'compact' themes available in Firefox, dark and light, based on the Firefox Developer Edition theme

  • Windows users can select 32-bit or 64-bit versions in the installer

  • On qualified Windows systems, a new 'compositor process' mitigates the risk of device driver related browser crashes


  • Windows XP and Vista are no longer supported. XP and Vista users running Firefox 52 will continue to receive security updates for another year.

  • 32-bit Mac OS X is no longer supported. Firefox is now a 64-bit only Mac OS X application

  • Updates for Mac OS X are smaller in size compared to updates for Firefox 52

  • Ended Firefox Linux support for processors older than Pentium 4 and AMD Opteron

  • Refresh of the media controls user interface

  • Shortened titles on tabs are faded out instead of using ellipsis for improved readability

  • Media playback on new tabs is blocked until the tab is visible

  • Permission notifications have a cleaner design and cannot be easily missed


  • Changes for web developers

  • Support for WebM video with alpha, which allows playing videos with transparent backgrounds

Developer Information