I use Firefox as my default browser on macOS Catalina version 10.15.7. Yesterday I used
brew to upgrade Firefox to the latest version:
brew upgrade firefox
After the upgrade, Firefox works normally when I open it from applications menu. It is the latest version:
However since the upgrade, links in my mail through the Apple Mail app don't open. When I click on them, nothing happens. If I right click the link and select "open with" and choose Firefox, I get a dialog that says:
You can't open the application "Firefox" because the Classic environment is no longer supported.
When I search for this error message, it appears to be related to application that are not compiled for macOS. I shouldn't think that would apply to Firefox.
It appears that a second older version of Firefox 89.0.2 was still installed on my system in
/usr/local/Caskroom. I found it with the command
locate firefox and then I removed it, but it didn't solve the problem.
locate firefox and
locate Firefox now only show firefox installed in
What is causing this error and how can I fix it?
This has something to do with
brew. I just tried installing Google Chome from brew because it also needed to up updated. (Neither Firefox nor Chrome have the permissions needed to update themselves.) I used the
-f flag to force brew to overwrite the version of chrome that had been installed in some other way:
brew install google-chrome -f
After installing Chrome from brew, Mail can't open links in it either with the same message. Is brew putting some wrapper around these applications that is using classic mode?