Assegnate 4 su 5 stelle

My Thunderbird has recently been updated to v.68.3.1(32 bit).
After that the sender[@] does not appear at the inbox, although its box is ticked in the settings. Before it did without problems.
When I select another folder, e.g. sent or garbage can, it shows sender[@] there and after return to inbox also there !

I tried to fix the problem with deinstalling the addon, closing Thunderbird, starting it again and installing the addon again followed by closing and restarting Thunderbird. Still same problem.

It is clear that a work around is like described above, but it should work as before the update.