Yes you are right, I know this one.
The broken informations are in the properties only.
The problem came from the fact the properties are stored in a JSON string. And when you remove a FK that has been used as group by property (for example), the group by properties behind to this removed FK are still present. The cascad deletion can not work because of the JSON string which is impossible to search in.
It is a big deal for me.
It do not create a fatal at the building, or in your generated component.
But I know it is really problematic.
This ticket will remain open a while for the moment I don't have any easy solution.
KEEP IN MIND :
Removing the FK can create issues in the properties of objects where this FK has been used.
-> Group by properties of Form > FK
-> Group by properties of Filters > FK
-> Group by properties of Grid