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.

Firefox Release

October 20, 2016

Version 49.0.2, first offered to Release channel users on October 20, 2016

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


  • Asynchronous rendering of the Flash plugins is now enabled by default. This should improve performance and reduce crashes for sites that use the Flash plugin. (Bug 1307108)


  • Change D3D9 default fallback preference to prevent graphical artifacts (Bug 1306465)

  • Network issue prevents some users from seeing the Firefox UI on startup (Bug 1305436)

  • Web compatibility issue with file uploads (Bug 1306472)

  • Web compatibility issue with Array.prototype.values (Bug 1299593)

  • Various security fixes


  • Diagnostic information on timing for tab switching (Bug 1304113)

All Firefox downloads