Rated 4 out of 5 stars

per Axel Dürrbaum el nov. 12, 2024 ·

Since three days switching is not possible any more
"Thunderbird is already running, but is not responding. To use Thunderbird, you must first close the existing Thunderbird process, restart your device, or use a different profile."

System:
Debian/12.7
Thunderbird 115.16.0esr (64-Bit)

This review is for a previous version of the add-on (3.5). 

per Dillinger (desenvolupador) a nov. 13, 2024 ·

Could be a stale thunderbird in the background, try "killall thunderbird" or "killall thunderbird-bin" in a terminal.
If that doesn't work send me an email, this is not a good place for support.