Comment 66 for bug 411358

So how about limiting the scope of the fix even further? It seems that the majority of the complaints are about patterns where the plus sign follows straight after the colon. While there are no registered URL protocols which start with a plus sign, it strikes me as awfully ad-hoc; but it should certainly limit the scope of this bug significantly. On the other hand, you'd still be affected if you receive emails with svn+ssh:// links in them.

On the other hand, if Ubuntu is the problem, how about submitting the patch to https://bugs.launchpad.net/ubuntu/+source/thunderbird/+bug/411358 instead? (They are awful at accepting patches for Firefox at least, but if the problem is squarely with their packaging, I hope it could be accepted.)