RFC 6454 "The Web Origin Concept" [defines origin serialization algorithms](https://tools.ietf.org/html/rfc6454#section-6), but [so does the HTML spec](https://html.spec.whatwg.org/multipage/browsers.html#unicode-serialisation-of-an-origin). Given that RFC 6454 is cited normatively elsewhere in the HTML spec, it seems like either it should be cited again here or else the relationship between the definitions (willful violation?) should be noted. The definitions looked to be the same, with the exception of the phrasing of the "domain to ASCII" and "domain to Unicode" steps, but I'm not familiar enough with the area to be able to determine whether the difference is actually substantive.