Update on my Irish-accented domain woes: "Let's Encrypt" support IDN domain names, so I can get a cert, but they only accept them in the "wat" Punycode format. Caddy might support doing better but right now it's strictly speaking serving the Punycode version of the domain, and proxying the punycode version to the fedi software I'm trying to run, epicyon.
And epicyon is comparing the actual domain to the punycode version and rejecting it outright.
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