RFC 5891, "Internationalized Domain Names in Applications (IDNA): Protocol", August 2010Source of RFC: idnabis (app)
Errata ID: 3969
Status: Held for Document Update
Publication Format(s) : TEXT
Reported By: Peter Occil
Date Reported: 2014-04-19
Held for Document Update by: Barry Leiba
Date Held: 2014-04-21
Section 22.214.171.124 says:
The Unicode string MUST NOT begin with a combining mark or combining character (see The Unicode Standard, Section 2.11 [Unicode] for an exact definition).
It should say:
The Unicode string MUST NOT begin with a combining mark or combining character (as defined in The Unicode Standard, Section 3.6 [Unicode], definition D52).
Section 2.11 of the Unicode Standard explains what combining characters are only in general terms. Section 3.6 contains the actual definition.
----- Verifier Notes -----
The actual fix is probably closer to changing "exact definition" to "explanation of combining characters," and leaving the reference alone. But discussion indicates that more clarification is probably good, and that clarification needs to be in the broader context of a document update.