Rated 4 out of 5 stars

Previous version (6.2.1) worked for me.

Rated 1 out of 5 stars

Thunderbird 78.6.0, 64-bit, Polish interface
I don't see any new button/icon/entry in menu or toolbars.
TB displays "TB thinks it is a spam" message bar twice instead.
This add-on doesn't work at all for me.