IPv6 address encoding in commonName

[Salz, Rich]

    RFC 8002 (with a null subjectName), but a CA cert MUST have a non-empty 
    subjectName.

Non-empty subjectName or non-empty commonName within the subject name?

Shrug.  Doesn't matter, I guess.  Just populate it with the string version of the HIT name, something like
	CN=IP Address 2001:27:dcfc:cb8:d53g:5364:48bj
?

>    My searches today have come up empty.
  
I tried crt.sh and also came up empty; https://crt.sh/?CAName=%25%3A%25  This is not surprising since I would not expect any public CA's to have this kind of thing.