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.

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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 66.0.1, first offered to Release channel users on March 22, 2019

Various security fixes

Reference link to 66.0 release notes

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

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Firefox Release Notes

66.0.1 Firefox Release

Fixed

Get the most recent version