Keeping Yosemite Alive: How to Download Firefox for Mac 10.10.5
Last verified for compatibility: May 2026. Mozilla may remove older builds from archives, but the paths mentioned remain valid as of this writing. For commentary on legacy Mac browsers, check the r/firefox and r/macos subreddits.
Downloading Firefox 78 for an aging Mac is an act of digital preservation. It allows an old friend to continue "buying cat food and banking," as one archivist poignantly put it. It is the difference between a functional tool and a beautiful aluminum brick. We keep these machines not because we can't afford the new, but because the old still works, its keys worn smooth by years of shared history. In a world of planned obsolescence, choosing to find that one compatible installer is a small, quiet rebellion—a way of saying that even in the digital age, some things are worth keeping around. firefox download for mac 10105 upd
The latest and final version of Firefox that works on Mac OS X 10.10.5 is Firefox 78 Extended Support Release (ESR) Mozilla Support Current Status
Locate the downloaded .dmg file in your Downloads folder and double-click it. Keeping Yosemite Alive: How to Download Firefox for Mac 10
If you are still running OS X Yosemite (10.10.5) and trying to get the latest version of Firefox, you have likely hit a wall. Modern software moves fast, and support for older operating systems eventually falls by the wayside.
Direct download link (official Mozilla source):
https://ftp.mozilla.org/pub/firefox/releases/78.15.0esr/mac/en-US/ Downloading Firefox 78 for an aging Mac is
Official Mozilla Archive: You can find the specific installer on the Mozilla Release Archive.