Currently you are not able to use $nick@duck.co for XMPP. There is no such
thing as a domain alias in XMPP, so $nick@dukgo.com and $nick@duck.co
are separate accounts in XMPP, and always will be.

We may provide a way to use $nick@duck.co in the future but nothing like that is planned as of yet.
posted by jaryd Staff4 years and 2 months ago Link