Changing the application that opens link in Mozilla Thunderbird 2.0, as I recently discovered, is not trivial (at least not in Linux). I’m doing this using Mandriva 2007.1 Free, so other distributions may handle this differently.

Here’s what I had to do to get Thunderbird to open URL’s in Firefox.

1) Open Thunderbird, then go to the menu option Edit->Preferences. A window will open, now select the ‘Advanced’ option at top, and then click the ‘Config Editor’ button near the bottom.
2) search for the Preference Name called On Mandriva this points to /usr/lib/thunderbird-2.0b2/open-browser-sh
3) If you open the file /usr/lib/thunderbird-2.0b2/ you will see its a shell script that checks gconf to see what browser should be used (I don’t know why they make this so difficult). There was a comment in the script that said the default browser was stored in the gconf key ‘/desktop/gnome/url-handlers/http/command’
4) To see what the current application being used is: gconftool -g /desktop/gnome/url-handlers/http/command
Now you are ready to set this key to use a new application, run the following command:
gconftool –type=string -s /desktop/gnome/url-handlers/http/command ‘/usr/bin/firefox “%s”‘

Thats all you should have to do, you don’t have to restart Thunderbird as the settings should take effect immediately. I hope that soon Thunderbird makes this much much easier.

*Note: One other option you might try doing is when you have opened up the Thunderbird Config window, you might be able to edit the value of and set it to the location of your preferred browser. I have not tried doing it this way so I can’t be sure if this would work, though I suspect it would.

The Thunderbird config window looks like this:
Thunderbird 2.0 Config window