It seems like editing /usr/share/xfce4/helpers/firefox.desktop fixes this bug (as suggested in https://bugzilla.mozilla.org/show_bug.cgi?id=1080319#c39); not only for thunderbird, but also for xfce4-terminal and apport-bug. Redirecting this bug to the package libexo-helpers and marking the other two as duplicates.
** Bug watch added: Mozilla Bugzilla #1080319 https://bugzilla.mozilla.org/show_bug.cgi?id=1080319 ** Package changed: thunderbird (Ubuntu) => exo (Ubuntu) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1429275 Title: Thunderbird does not open http URL anymore with Firefox v36.0 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/exo/+bug/1429275/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
