@mmn thanks for the feedback.

I didn't know GNUsocial can direct mention URLs now. Does that feel strange from a UI perspective? Do many use it?

My original thought was to include the @ just to make recognizing mentions a bit easier, and thus, yeah, if anyone allows '.' in the username, it gets a bit more complex. So far it looks like Friendica does support it, but doesn't recommend it as its known to be an issue with federating.