8.6
78.15.0esr is the last real, stable “upd” for Mac 10105.
Open your folder and double-click the downloaded .dmg file.
Apple released macOS Yosemite (10.10) in 2014. Because it is no longer supported with security updates by Apple, mainstream browsers like the current Google Chrome or the latest Firefox (e.g., version 151+) will not install or function properly. firefox download for mac 10105 upd
Once the file download finishes, locate it within your local machine's Downloads folder to complete the local environment setup:
For users on Mac OS X 10.9, 10.10, and 10.11, the "end of the road" was . Because it is no longer supported with security
Before installing, check that your Mac hardware aligns with these legacy requirements: Specification Mac OS X 10.10.5 (Yosemite) Exact Software Version Firefox 78.15.0esr File Format Apple Disk Image ( .dmg ) Architecture Intel 64-bit Last Security Update October 5, 2021 Managing Performance and Limitations on OS X 10.10.5
A: Mozilla has not announced any immediate plans to drop support for macOS 10.15. Since Firefox 116.0, Catalina has been the minimum requirement, and it remains fully supported. However, as macOS evolves, support for older operating systems may eventually be phased out. For now, Catalina users can continue using the latest versions of Firefox without concern. Since Firefox 116
If macOS prevents the app from opening, go to and click Open Anyway . Critical Support Information How to update outdated browser on OS X Yosemite
