Does Twitter allow arabic usernames?

This is a non-standard, non-alpha-numeric, Arabic Twitter handle! This is the handle and not the username. Usernames concern themselves with the bio. A handle is the URL suffix for used to identify an account, like the following:
twitter․com/‏ميمي العنزي
After Mikko's tweet, several people, including myself, tried to reproduce this anomaly. It turns out, there is little if any documentation on how, or even why this happened. I think in some rare cases, Twitter shows accounts in arabic that start with 0x. Like
I've yet to reproduce this behaviour on Twitter though. One of my favourite replies to Mikko's tweet was by Mathias Bynens

@mikko Technically every Twitter handle has Unicode in it.

— Mathias Bynens (@mathias) May 12, 2013