Hello @Canapin 
My forum is in Turkish. There is a Turkish character named group slug. However, since the use of ASCII characters in the URL is active, this is not a problem. There are already other groups that contain Turkish characters. My problem is actually right now: I have two groups that are giving 404 error on the Groups page and I want to delete them. How can I delete?
No problems other than grouping. I can actually create groups now.