Yep, this is the right way to suggest a new draft! Thanks for writing this
up.
One high-level comment on a quick skim: I don't think you need the new
identifier type. Since .onion is a "legit" TLD [RFC7686], onion names are
part of the DNS namespace. It's OK for CAs to have different policies f
I don't think we can change challange name while being competiable with
CABF reqs: they already point to RFC8555 section 8.3 and RFC8723 for
allowed challanges. any other name will not be comply with that.
we can invent new http based challange based 4.3.3.2.18, but it will
have to use differe