aslakr, 7 months ago

@osma Maybe https://datatracker.ietf.org/doc/html/rfc7565#section-6

> o The userpart consists only of Unicode code points that conform to the PRECIS IdentifierClass specified in [RFC7564].

and https://datatracker.ietf.org/doc/html/rfc7564#section-5.2.3 ?