Mozilla Support में खोजें

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

How to downgrade a Firefox install on old iMac (late 2009) when I can't open browser?

  • 1 प्रत्युत्तर दें
  • 0 यह समस्या है
  • 11 views
  • के द्वारा अंतिम प्रतियुतर cor-el

more options

Hi, the turbotax website forced me to update Firefox and since I did, I am no longer able to open the browser at all. The error message reads, "You can't use this version of the application "Firefox" with this version of OS X. You have OS X 10.11.6. The application requires OS X 10.12 or later." Unfortunately, from what I have read, I can't get that update that on my iMac (21.5inch, late 2009) OS X El Capitan Version 10.11.6. Is there any way to downgrade the Firefox install? I can't even see what previous version of Firefox I had before because I can't open the browser anymore. If anyone can help I would be super grateful. Thanks in advance!

Hi, the turbotax website forced me to update Firefox and since I did, I am no longer able to open the browser at all. The error message reads, "You can't use this version of the application "Firefox" with this version of OS X. You have OS X 10.11.6. The application requires OS X 10.12 or later." Unfortunately, from what I have read, I can't get that update that on my iMac (21.5inch, late 2009) OS X El Capitan Version 10.11.6. Is there any way to downgrade the Firefox install? I can't even see what previous version of Firefox I had before because I can't open the browser anymore. If anyone can help I would be super grateful. Thanks in advance!

All Replies (1)

more options

Firefox 78.15.0 ESR is the last version for Mac OS X 10.9/10.10/10.11 (distributionID: mozilla-mac-eol-esr1) and you will no longer receive updates.

Firefox 78.15.0 on the Mozilla CDN server:


Mac OS users on OS X 10.12/10.13/10.14 have been moved to the 115 ESR update channel since this platform no longer is supported, current releases require macOS 10.15 as a minimum.