@nprofile1q...
It's complicated™️. Depending on the Unicode/stringprep/PRECIS specification level supported by your client and server, it's either allowed or forbidden. I'm working on a blog post describing all the relevant aspects, and I guess the full description will cover over a dozen RFCs.

@nprofile1q...
The punycode host name would be xn--e4h.op-co.de but when establishing an XMPP link, you need to tell the server the Unicode version of the domain inside the XML stream, so if your implementation doesn't support it, you'll be out of luck. I also have xmpp:ツ.op-co.de which doesn't violate IDNA2008 if you want to test.

@nprofile1q... In fact, I was just pointed out that ☝️ is forbidden under IDNA2008 rules, but it was allowed under IDNA2003, so apparently the Unicode consortium DOES NOT WANT US TO HAVE FUN!!!

That said, the different skin tones are encoded with Fitzpatrick Modifiers, e.g.

U-1F3FF EMOJI MODIFIER FITZPATRICK

which were only introduced in Unicode 8.0 in 2015, so long after both IDNA2003 and IDNA2008. The former treats them as unassigned, not sure about the latter.

@nprofile1q...
Today for the whole day there was a queue outside for the day passes (no idea how long it takes though), but you only need them to enter the building for talks / hack space / the bar. Hanging out outside on the meadows or getting food works without a pass. Ping me if you decide to come, I'll be there from noon to the evening.

@nprofile1q...
I've been mad about this bug for the last weeks as well (also evince seems to take much longer to load now?), but I thought that was yet another "UX" "improvement" from the Gnome team... So decided not to do anything about it...