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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66.0.5
Firefox Release

May 7, 2019

Version 66.0.5, first offered to Release channel users on May 7, 2019

Fixed

Get the most recent version

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

Your system doesn't meet the requirements to run Firefox.

Your system doesn't meet the requirements to run Firefox.

Please follow these instructions to install Firefox.

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