Description of problem: Mozilla Thunderbird has no any preinstalled setting for opening http:// or https:// links. Thus, user should know, how to select firefox for this action (he will forced to type /usr/bin/firefox in the appropriated field). It is not very usable, and many users will have problems with this. How reproducible: Aways. Steps to Reproduce: 1. Install latest Mozilla Thunderbird. 2. Set up any your email account. 3. Read any mail in HTML with the hyperlink and try to click on it.
According to this comment http://bugs.rosalinux.ru/show_bug.cgi?id=180#c10, I suppose that rebuilding thunderbird with "--enable-gio" can help.
This bug seems to have the same reason as bug #380 - Thunderbird uses gio, but we just don't have necessary associations in out shared-mime-info package. *** This bug has been marked as a duplicate of bug 380 ***