Originally posted by raysr
cat: command not found
You don't need the "cat" command. I just used it to print
the info to stdout quickly so I could paste it here for you.
If you can't seem to find .thunderbird run "updatedb" as root,
and then as a normal user run "locate .thunderbird" and that
should give you the location.
However you go about editing files, open the editor and then go
to wherever your distro installs the Thunderbird preferences, and
you'll find the directories under there. When you find your file, it's
okay to copy what I posted before and paste it into your file. Then
save the file, close and relaunch Thunderbird. Then you should be
able to click on an URL within Thunderbird and have it launch Firefox.