Added support for Windows SSO, allowing users to log into Microsoft, Google, and other work accounts more seamlessly.
Because this version is no longer the "current" ESR, it is not available on the main Firefox download page. To find it, you must access Mozilla’s official FTP archives. firefox esr 91 download
Enterprise environments and legacy operating systems. Where to Download Firefox ESR 91 Added support for Windows SSO, allowing users to
Firefox 91 ESR introduced several significant shifts for enterprise users compared to its predecessor (ESR 78): Enterprise environments and legacy operating systems
The most secure version of this branch is 91.13.0esr . Download Steps: Navigate to the Directory Listing for 91.0esr.
Firefox ESR 91 Download and Installation Guide Firefox Extended Support Release (ESR) 91 was a milestone version designed specifically for schools, universities, and large organizations that require a stable, long-term browsing environment without frequent feature updates. While newer versions are now available, Firefox ESR 91 remains a common search for users maintaining legacy systems or specific enterprise configurations. Quick Facts: Firefox ESR 91 August 10, 2021 Final Planned Release: Version 91.13.0 (August 23, 2022)