I framed my only major point as a recommendation, not a requirement, and that recommendation was, effectively, declined in subsequent emails.

So, I'll reduce that (over) long screed with my points (b)--(d):

  b) Replace the first two bullets in the algorithm description, with

         * JSON-encode the array, producing a UTF-8 byte sequence.

         * base64url-encode the resulting byte sequence. The resulting
           string is the Disclosure.

      c) Be careful never to use "string" when "(UTF-8) byte sequence"
         is meant, starting in 4.2.2 with

           The Disclosure string is created by JSON-encoding this array
           and base64url-encoding the resulting byte sequence as
           described in Section 4.2.1

      d) In the second media type registration in 12.2
           "represented as a JSON Object" ->
           'represented as UTF-8 encoded "JSON text" as defined in [RFC8259]'