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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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

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Version 38.4.0, first offered to ESR channel users on November 3, 2015

Various security fixes

Developer Information

Get the most recent version

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

All Firefox ESR downloads

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Firefox ESR
Release Notes

38.4.0 Firefox ESR

Fixed

Developer

Get the most recent version