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

August 13, 2015

Version 40.0.2, first offered to Release channel users on August 13, 2015

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


  • Enabled API allowing Windows 10 users to open settings dialog (1193196)


  • mozalloc.lib was missing from the xulrunner package (1168291)

  • Fix a startup crash with some combination of hardware and drivers (1160295)

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