Something has changes with information_schema in MySQL 8 that prevents heidisql from being able to read most of the tables. It's frustrating as I use it quite heavily for my migration and code generation tools.
It's not only heidisql that is effected, some other connectors and libs also break with information_schema in mysql 8 so if anyone figures out what's causing it please share.
The client works alright so I would guess the issue is in the diffs for that.