Sadly it looks like that wont work either, because Lemmy considers “ab_dl” and “abdl” to be the same community name, so I can’t make a new community without the underscore, I geuss.
I think the only way to remove the underscore would be to rename or remove the existing community from the database. But I’m not sure. I’ve send yay a PM asking if there’s any possibility of that, but if not I might be out of luck.

Oh, I see. Thanks a lot for the help!