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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.

91.4.1 Firefox ESR

December 16, 2021

Version 91.4.1, first offered to ESR channel users on December 16, 2021

Fixed

  • Fixed frequent MOZILLA_PKIX_ERROR_OCSP_RESPONSE_FOR_CERT_MISSING error messages when trying to connect to various microsoft.com domains (bug 1745600)

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