The firefox download for mac 10105 upd is a very specific necessity. By downloading Firefox 78.15.0 ESR directly from Mozilla’s FTP server, you can breathe another year or two of life into your Mac running OS X Yosemite 10.10.5.
While this setup is not recommended for primary, secure daily driving, it is the best possible modern browsing experience available for your legacy hardware. Keep your expectations realistic, use a robust ad-blocker, and consider upgrading your machine at the earliest opportunity.
Download Link Summary:
If this guide helped you, consider donating your old Mac to a school or recycling it properly. Legacy software can only patch security holes for so long.
For users on macOS 10.10.5 (Yosemite) , the latest supported version of Firefox 78.15.0 ESR
. Modern versions of Firefox (version 79 and higher) require macOS 10.12 or newer. Mozilla Support Key Compatibility Details Final Version
: Firefox version 78 was the last to support OS X 10.9 Mavericks, 10.10 Yosemite, and 10.11 El Capitan. Security Status : Support for this version ended in October 2021
. It no longer receives security updates, meaning using it may expose your system to vulnerabilities. Modern Requirements : Current Firefox releases require a minimum of macOS 10.15 Mozilla Support How to Download and Install Since the main Mozilla Download Page
will automatically offer the newest (incompatible) version, you must manually download the older installer: Access the Archive : Visit the Mozilla FTP Archive or use the Mozilla directory of other versions Select the Build : Choose the 78.15.0esr release specifically for Mac. : Open the downloaded file and drag the Firefox icon into your Applications Security Prompt
: If macOS blocks the app because it's from an "unidentified developer," go to System Preferences > Security & Privacy Open Anyway Mozilla Support Troubleshooting Tips If Firefox Won't Open
: Ensure you haven't accidentally downloaded a newer version. Check the version by selecting About Firefox in the menu. "Up to Date" Messages firefox download for mac 10105 upd
: 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
: If you need a more modern browsing experience on 10.10.5, consider the Legacy-Video-Player
or other community-backported browsers, though upgrading your macOS is the only way to get a fully secure Firefox. Mozilla Support compatible browser
that still receives security updates for older macOS versions? Update Firefox to the latest release - Mozilla Support
How to Download Firefox for Mac OS X 10.10.5 (Yosemite) If you’re still using a classic Mac running OS X 10.10.5 Yosemite
, you may have noticed that many modern browsers no longer support your operating system. However, you can still get a functional and relatively secure version of Firefox to keep your machine surfing the web. The Last Compatible Version: Firefox 78 ESR
For users on Mac OS X 10.10.5, the most up-to-date official version available is Firefox 78 Extended Support Release (ESR)
. This was the final major release to support Yosemite before Mozilla moved its minimum requirements to macOS 10.12 Sierra and later. Firefox 78.15.0esr
This version is no longer receiving security updates as of October 2021. Why use it?
It is generally more compatible with modern websites than the outdated version of Safari that comes with Yosemite. Step-by-Step: How to Download and Install Since the main Firefox Download Page The firefox download for mac 10105 upd is
will automatically try to give you the newest version (which won't open on 10.10.5), you need to follow these steps: Locate the Correct Installer : You can find older versions on the Mozilla CDN server or through reputable archives like Download the DMG : Save the Firefox 78.15.0esr.dmg file to your Downloads folder. : Open the DMG file and drag the Firefox icon into your Applications folder
: Open your Applications folder and double-click Firefox. If you see a warning about an app "downloaded from the internet," click Important Tips for Legacy Users Security Risks
: Because Firefox 78 ESR has not had security patches in years, avoid using it for sensitive tasks like online banking. Website Issues : If a site looks "broken," it might be due to Enhanced Tracking Protection . Click the shield icon
in the address bar to try disabling it for that specific site. Upgrade Options : If your hardware allows it, consider upgrading your OS to 10.11 El Capitan 10.13 High Sierra . High Sierra supports Firefox 115 ESR
, which remained supported with security updates much longer.
For users on Mac OS X 10.10.5 (Yosemite) , the journey to a modern browsing experience has a specific finish line. Since 2021, Mozilla has officially ended support for this operating system version, but there is still a way to get a compatible version running. Apple Support Community The Recommended Version: Firefox 78 ESR
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
: This version is no longer receiving security updates as of October 2021. Functionality
: While it can still browse many websites, some modern features or highly secure sites may encounter compatibility issues. Apple Support Community How to Download and Install
Since the main Firefox download page will typically offer the newest version (which requires macOS 10.15 or later), you must use the official archive for the older version. Mozilla Support Download the Installer : Access the Official Mozilla Archive for 78.15.0esr to download the Open the DMG If this guide helped you, consider donating your
: Double-click the downloaded file to open the installer window. : Drag the Firefox icon Applications folder
: Open Firefox from your Applications folder. You may need to click "Open" on a security prompt since it is an older software package. Mozilla Support Why You Can't Get Newer Updates
Mozilla moved users on OS X 10.9, 10.10, and 10.11 to the Extended Support Release (ESR) channel to provide a few extra years of security. However, maintaining support for decade-old operating systems became unsustainable as web technologies evolved. Mozilla Support Better Alternatives for Your Mac
If your hardware allows it, experts recommend upgrading your macOS to at least 10.15 Catalina
or higher to use the latest, most secure version of Firefox.
Since the browser engine is outdated, you need to block malicious scripts. Install uBlock Origin from the add-ons store. It will still work on version 78.
For users on legacy operating systems like Yosemite, Mozilla provides a special branch called ESR (Extended Support Release). Unlike the standard consumer version that updates every four weeks, ESR focuses on stability and security patches for enterprise users—and incidentally, for old Macs.
Key details of Firefox 78 ESR for Mac 10.10.5:
As of late 2024, Mozilla Firefox has ended support for Mac OS X 10.10 (Yosemite).
If you try to download the standard installer from the main Mozilla homepage, you will likely receive a message that your operating system is incompatible.
The last supported version for OS X 10.10.5 is Firefox 78.15.0 ESR.
Solution: Your current browser may have malware or an old search engine hijacker. Install fresh Firefox 78.15 and run a scan with Malwarebytes for Mac (compatible version 4.17).