IDN with Gemini?

[Stephane Bortzmeyer]

On Mon, Dec 07, 2020 at 09:46:06PM +0000,
 colecmac at protonmail.com <colecmac at protonmail.com> wrote 
 a message of 49 lines which said:

> Despite what this RFC says, I don't see what situation would actually
> completely fail on punycoded domains. I guess the spec could mandate trying
> with punycode first, than Unicode, but that seems needless to me. Do you
> have an example of a system/network that fails on punycode?

mDNS (used in Apple's Bonjour). Despite its name, it has little to do
with DNS, and it requires UTF-8 (and does not use Punycode).

gemini://gemini.bortzmeyer.org/rfc-mirror/rfc6762.txt