I have recently moved from the version of Thunderbird that came with Ubuntu 18.04 to a download of Beta from https://www.thunderbird.net/en-GB/, mainly because “Beta is better”(!). I have installed it and have moved my profile across and all looks okay, but I am having one small niggling problem.
I have the GNOME desktop environment, with the GNOME dock. In the same way that I added a Mozilla build of Firefox Nightly, I have added a .desktop file to add Thunderbird to the dock. The contents of the file (based on what I know works fine for Firefox Nightly) are:
Comment=Send and receive mail with Thunderbird
The (new) icon does appear, and looks great, but whenever I run Thunderbird, it appears as a second icon at the bottom of the dock, not run from the one I have selected, despite the %u flag to the Exec.
Has anyone any ideas on how I can fix this?