Thank you for updating the .desktop file. The issue is more hairy than it seems at first glance. E.g. https://debbugs.gnu.org/ sends "Content-disposition" header with ".mbox" suffix when a single comment in mbox format is requested (to reply to particular message). Thunderbird believes that a suitable action is to compose a new message with downloaded file as an attachment.
There is no command line option to force thunderbird to open a file as namely mail message. The position of developers is that such file must have ".eml" extension otherwise it is not a message. See https://bugzilla.mozilla.org/show_bug.cgi?id=1755454 for details (bug title has been changed to fix a loosely related issue). ** Bug watch added: Mozilla Bugzilla #1755454 https://bugzilla.mozilla.org/show_bug.cgi?id=1755454 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1861262 Title: Add message/rfc822 to thunderbird.desktop To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/thunderbird/+bug/1861262/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
