Had  some trouble today with the site and deleted everything from the NAS thinking it was at fault.
In fact, it was my router – probably running its last legs.

Anyway, it was a great opportunity to clean things up, I jettisoned everything, reinstalled fresh software, only WordPress and MariaDB10, not bothering with phpMyAdmin anymore and all is well, faster than before.
I also cleaned the WordPress modules I do not use, I didn’t even remember what some of them were doing.

And finally, I removed completely my WordPress site on wordpress.com, it was useless anyway since plugins are not allowed on free accounts.