Mental illnesses aren't curse words and shouldn't be treated as if they were. Of course joking about it should be dealt with yet more of a mute or warn not a full on ban for crying out loud for usernames not at all since it can be hard to tell. If someone was harassed about a mental illness because A they have it or B they say they have it such as the r word if you know what I am talking about. That would then file under harassment.
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