Firefox ESR
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.

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Firefox is no longer supported on Windows 8.1 and below.

Please download Firefox ESR (Extended Support Release) to use Firefox.

Download Firefox ESR 64-bit

Download Firefox ESR 32-bit

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Firefox is no longer supported on macOS 10.14 and below.

Please download Firefox ESR (Extended Support Release) to use Firefox.

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Version 78.3.1, first offered to ESR channel users on October 1, 2020

Fixed legacy preferences not being properly applied when set via GPO (bug 1666836)

Developer Information

Reference link to 78.3.0 release notes

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Download Firefox — English (US)

Your system may not meet the requirements for Firefox, but you can try one of these versions:

Download Firefox — English (US)

Firefox is no longer supported on Windows 8.1 and below.

Please download Firefox ESR (Extended Support Release) to use Firefox.

Download Firefox ESR 64-bit

Download Firefox ESR 32-bit

Download a different build

Firefox is no longer supported on macOS 10.14 and below.

Please download Firefox ESR (Extended Support Release) to use Firefox.

Download Firefox ESR

Firefox Privacy Notice

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Firefox ESR
Release Notes

78.3.1 Firefox ESR

Fixed

Developer

Get the most recent version