Firefox Legacy
Mac OS X users of Firefox who still use these older versions of the Mac OS X operating system will be able to use Firefox ESR for another year before support runs out. It is unclear if and how other Firefox channel installations, e.g. Firefox Nightly or Beta, are affected by Mozilla's decision to end support. Firefox 48 is the last Firefox version to support Mac OS X Snow Leopard, Mac OS X Lion, and OS X Mountain Lion. Additionally, support for old processors without SSE2 extensions such as the AMD Athlon XP and Pentium III was dropped. Firefox 49 was released on September 20, 2016 for both desktop and Android. Firefox is designed to ensure that only one copy of Firefox is using a profile at a single time. To ensure this, it places special lock files in the profile directory. In rare cases, Firefox could have left behind the lock file when it crashed or quit abnormally.
Firefox Legacy is an unofficial modified version of Mozilla Firefox that works on older Mac OS X versions, including 10.6 Snow Leopard, 10.7 Lion, and 10.8 Mountain Lion.
Download it now and breathe new life into your old Mac.
Firefox For Mac Os
OS X 10.8 Mountain Lion
Current version for OS X 10.8 Mountain Lion: 71.0p2 (2020-09-15)
IMPORTANT NOTE ABOUT UPDATING TO v71: A new Firefox profile will be created when you update from earlier versions to version 71.0. To restore your previous data, type 'about:profiles' in the address bar, then find your previous profile (if you can't tell which, try each one) and set it as default. Then, restart Firefox Legacy. I apologize for the inconvenience; the cause of this issue is not known.
OS X 10.7 Lion
Current version for OS X 10.7 Lion: 68.12.0p3 (2021-01-24)
Now featuring support for numerous newer web standards, including Push, Service Workers, Feature Policy, ResizeObserver, Promise Rejection Events, more of the Animations API, and several CSS features. This should improve compatibility with many websites.
For security and privacy reasons, starting in version 68.12.0p3, support for TLS 1.0 and 1.1, HPKP, and the Battery API is disabled.
OS X 10.6 Snow Leopard
Only Firefox 52 is available for OS X 10.6 Snow Leopard; it will not be updated to a recent version due to technical limitations of the OS.
Note: the program is called 'Nightly' due to licensing restrictions prohibiting the use of the official Firefox branding.
Current version for OS X 10.6 Snow Leopard: 52.9.1p1 (2020-04-11)
Firefox Legacy speaks your language!
Any of the language packs for the matching official Firefox version are supported.
- List of language codes (to help you locate the right file to download)
Firefox For Older Mac
Known Issues
Firefox For Old Pc
- Small problems with displaying right-to-left languages on OS X 10.7
- The crash reporter does not work on OS X 10.7 or 10.8 (it itself crashes)
- A useless empty share menu is visible on OS X 10.7
- The sandbox (a security feature intended to protect you from malicious websites) does not work, and has been disabled
- On OS X 10.7, the browser crashes when the camera or microphone are used
- WebGL does not work on computers with GPUs not supporting OpenGL 3.0 (many 2006-2007 Macs)
- Some buttons are invisible on Google Calendar, WordPress, and other sites that use font-based icons
- DRM (Encrypted Media Extensions/Widevine) does not work
- Version 68.12.0 only: Screen capture does not work and has been disabled
- Version 71.0 only: The progress bar is not visible on the icons of downloading files in the Finder