Thunderbird calendar mint 21

Hi, no problem. I must admit I’m not a fan of Thunderbird as a mail client. For what it’s worth, Gnome desktop integration with Google is now pretty good so I sync my standard Gnome calendar with my Google accounts and that seems to work quite well. (as does google drive, which appears as just “another” folder …)

I switched my mail client to Orbit quite some time ago, which also does Google calendar sync;