Firefox Beta and Developer Edition
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.

57.0beta Firefox Beta

September 26, 2017

Version 57.0beta, first offered to Beta channel users on September 26, 2017

In October of last year we announced Project Quantum, our effort to create a next-generation engine. Firefox 57 includes many aspects of this project, so we’re calling this release Firefox Quantum.

Firefox Quantum is roughly 2X faster than Firefox 49 on the Speedometer 2.0 benchmark, thanks to its new CSS engine, its “just right” multi-process architecture, the way it prioritizes your active tab, and much more. Firefox Quantum also includes a visual refresh – Photon – that looks and feels right at home with modern operating systems. To learn more about Firefox Quantum, visit the Mozilla Blog.

New

  • Firefox is getting a major Visual Redesign (Photon project) activated on the Nightly channel and which will ship with Firefox 57 on the release channel.

  • AMD VP9 hardware video decoder support for improved video playback with lower power consumption

  • Accessibility indicator will now appear in the title bar of the window when Accessibility services are enabled

  • Added support for Date/Time input

  • Allow users to manage the site data

Changed

  • The browser's autoscroll feature, as well as scrolling by keyboard input and touch-dragging of scrollbars, now use asynchronous scrolling. These scrolling methods are now similar to other input methods like mousewheel, and provide a smoother scrolling experience

  • The content process now has a stricter security sandbox that blocks filesystem reading and writing on Linux, similar to the protections for Windows and macOS that shipped in Firefox 56

  • Middle mouse paste in the content area no longer navigates to URLs by default on Unix systems

  • Removed the toolbar Share button. If you relied on this feature, you can install the Share Backported extension instead.

Developer

  • Developer Information

  • Complete visual refresh of both the Light and Dark DevTools themes, matching the new visual style of Firefox Quantum

  • The Inspector shows the values of CSS variables on hover

  • Completely new and re-designed Console panel. Joining the Debugger and the Network Monitor, the Console has been rewritten using modern web technologies such as React and Redux. It now also allows inspection of objects in context.

Unresolved

  • On Windows and Linux, Firefox crashes occasionally on Intel Broadwell-U processors with old microcode. Windows users should ensure Windows Update is set to install updates. Linux users should ensure that the distribution package for Intel microcode is installed.

Get the most recent version

All Firefox Beta downloads