Duplicate tranlator tabs Thunderbird 91.5

[ggustaf]

Thunderbird 91.5 Linux
Highlight text, right click and click translate.
Two tabs appear:

TAB 1: Google Translate
TAB 2: WEB Translate

The WEB tab is dark mode.
The Google Translate tab is light mode.

Any idea why two tabs appear? Or how I created this monster?
Read on for the fix / work-around for this issue.

FIX: Remove WEB Translate from Thunderbird /w Tools ==> Add Ons.
Re-install WEB Translate into Thunderbird 91.5.
The two tab issue vanishes.
A separate window then appears for WEB Translate.

Interesting, I have some ideas but I'm not sure.
There is a bug in Thunderbird regarding opening Popup window (the one that shows when you click the toolbar icon).
If the toolbar is not available, for example when you use context menu in the Compose window.

Did you tried this in the compose window or in the message window?

Also, see Settings / Context menu / Open translation in - what do have set here?
Try to change it to "New window".