Support new Firefox XDG Base Directory compliant location at ~/.config/mozilla #8200
Description
This needs to be updated since Firefox 147 will support and default to XDG Base Directory specification for all new installs/profiles going forward.
https://www.phoronix.com/news/Firefox-147-XDG-Base-Directory
https://bugzilla.mozilla.org/show_bug.cgi?id=259356