Firefox 91.13.0 Esr Download _hot_ May 2026

This version includes critical fixes documented in MFSA 2022-35 , ensuring that users who could not immediately upgrade were protected against known exploits.

As the terminal release for the 91 series, it served as the bridge to Firefox ESR 102 , with eligible users eventually receiving automatic updates to the newer branch.

It maintains the "Proton" UI design introduced in Firefox 89, providing a modernized look with reduced visual clutter compared to older ESR versions like 78. Downloading Firefox 91.13.0 ESR firefox 91.13.0 esr download

As of , Firefox 91.13.0 ESR is officially at End-of-Life (EOL) . Firefox ESR schedule

You can find the installation files for various operating systems (Windows 32/64-bit, macOS, and Linux) in the Mozilla FTP directory for 91.13.0esr . This version includes critical fixes documented in MFSA

Firefox 91.13.0 ESR ( Extended Support Release) is the final planned update in the Firefox 91 lifecycle, released on . While newer ESR versions like Firefox 140.10.2 are the current standard as of May 2026, version 91.13.0 remains a critical legacy build for specific enterprise environments or older hardware configurations. Key Features and Security Fixes

Technical details and specific library requirements (such as GTK+ 3.14 for Linux) are detailed on the official Release Notes page . Compatibility and Support Status Downloading Firefox 91

The 91.13.0 release was primarily focused on , addressing high-impact vulnerabilities before the transition to the next ESR branch.