Big Sur Update & Firefox are not friendly.
I just recently updated my Macbook Air to Big Sur and downloaded Firefox to use as my default browser. Installation went smoothly and I am able to use the program as intended. When I click on an external link, an window pops up and tells I do not have permission to open the app and to contact my computer or network administrator for support.
I am not computer savvy when it comes to programming and would love any help anyone has to offer.
Well recently after the Big Sur was taken out, a lot of people did find problems on their mac. Interstingly for my iMac (Retina 4K, 21.5-inch, 2017) is working perfectly fine with the Big Sur update with Firefox as default browser.
Please see the links below for some help and guidance:
Common fixes - https://support.mozilla.org/en-US/kb/firefox-does-not-work-common-fixes
If you want to rollback firefox you can and you can do so by seeing the steps in the link below: https://support.mozilla.org/en-US/kb/install-older-version-firefox Rollingback does fix a lot of people's issues.
Hope I helped!