Developer reply by Toshi
Rated 3 out of 5 stars
The Add-on is very usefull. But, sadly, it does not work with Thunderbird 115, aka Supernova.
See below.
https://addons.thunderbird.net/thunderbird/addon/display-mail-user-agent-t/reviews/1171756/
It is working fine, so please review your environment and settings.
https://i.imgur.com/wVDFI5A.png
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