ld2ndR, you should execute:
$ sudo rm /usr/bin/mozilla-thunderbird
because mozilla-thunderbird is deprecated and only thunderbird should be used in future.
Anyway, this would bring us back to the thunderbird package. If mozilla-thunderbird was not created, the problem would be solved. Can anyone confirm this?
ld2ndR, you should execute: mozilla- thunderbird
$ sudo rm /usr/bin/
because mozilla-thunderbird is deprecated and only thunderbird should be used in future.
Anyway, this would bring us back to the thunderbird package. If mozilla-thunderbird was not created, the problem would be solved. Can anyone confirm this?