Firefox Download For Mac 10105 Upd [exclusive] May 2026

macOS 10.10.5 (Yosemite)

For users running , the most recent and final compatible version of Firefox is Firefox 78.15.0 ESR (Extended Support Release) . This version reached its final update on October 5, 2021, and is no longer receiving security patches from Mozilla. Download Instructions

Installation Steps

If you need a different language, navigate the Mozilla FTP directory to find your specific locale folder. : firefox download for mac 10105 upd

: Double-click the downloaded file to open the installer window. : Drag the Firefox icon Applications folder macOS 10

• Lightweight browser for older hardware.
• Familiar Firefox interface.
• Works with many legacy extensions (pre-Manifest V3).
• Can access modern websites with limitations (some will break).

: If your browser says it is up to date but websites aren't loading correctly, it is likely because the internal certificates of version 78 are expired. Alternative Options Lightweight browser for older hardware

no new security patches

Running Firefox 78.15 in 2026 means for Firefox-specific vulnerabilities (CVEs after Nov 2021 are unpatched). However:

Website Compatibility

: Many modern websites (like banking or high-security portals) may not load correctly or may flag your browser as "too old".

, it remains the most functional official version for your OS. Where to Download: You can find older versions in the Mozilla release archives or through reputable community repositories like the Macintosh Repository How to Install Download the DMG: Locate the installer for Firefox 78.15.0esr. Open the File: Double-click the downloaded Drag to Applications: Drag the Firefox icon into your Applications Confirm the Version: Open Firefox, go to the top menu, and select Firefox > About Firefox to ensure you are on version 78. Critical Security Warning