Running an older Mac with OS X 10.10.5 Yosemite doesn't mean you have to give up on web browsing. While modern, secure browsers often require newer operating systems, Firefox offers a pathway for older machines to stay functional.
Search for app.update.auto and toggle its boolean value to .
: Look for the file named Firefox 78.15.0esr.dmg .
Mozilla officially ended support for the Firefox 78 lifecycle in late 2021. It no longer receives security definitions, vulnerability patches, or privacy updates. firefox download for mac 10105 upd
To avoid corrupted packages or malware from untrusted mirror portals, you must source this specific version directly from Mozilla's historical server distribution network.
A final note on security: using an outdated browser on an unsupported OS is a significant security risk. If you must continue using your old Mac, be extremely cautious about the websites you visit, avoid online banking, and consider using other security measures. The safest long-term solution is to either upgrade your macOS or consider investing in newer hardware.
A: Yes. Firefox is configured by default to automatically download and install updates. You will be prompted to restart the browser when an update is ready to be applied. Running an older Mac with OS X 10
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
If you are running an older Mac with , downloading the latest version of Firefox from the main Mozilla homepage will not work. Modern versions of Firefox require macOS 10.15 (Catalina) or later.
Now that Firefox is installed, you can open it by clicking its icon in the Dock or by double-clicking it in the Applications folder. The first time you launch Firefox, you will be prompted to configure your preferences. You can choose whether to set Firefox as your default web browser, import bookmarks from other browsers, or customize your privacy settings. : Look for the file named Firefox 78
:Access the official Mozilla archive to download the compatible installer directly: Download Firefox 78.15.0esr (English US).
Older browsers can struggle with modern, script-heavy websites. Recommended Alternative Strategy
: Click on the file named Firefox 78.15.0esr.dmg to start the download. Install the Application :