How would an XMPP client and server work over non-clearnet domain names? (.bit, .emc, etc.)

I’m thinking of buying a non-clearnet domain name to host an XMPP server and I was wondering how I’d get an XMPP client, with its registration and connection screen requesting a server address/domain, to successfully integrate the same as any other clearnet address.

What would the roadblocks be? Would the user’s device have to be set up with the ability to access the .bit domains? Would the browser also? Or could it be achieved just on the XMPP client’s end, or the server’s end?

I’m not sure if the client, where it is hosted, has to be able to communicate with the non-clearnet server – or the person’s device has to be able to.