Robin stated that example wording can be found in the Ada specification.
The specific wording I quoted is allowed anywhere that a separator is, from 2.2(7.1/3) in the Ada 2012 RM.
 Robin explained how a higher level protocol like UAX9-HL4 might be used to implicitly insert such marks.
Not quite; the insertion of such marks would be conversion to plain text (UAX #9, Section 6.5) of text subject to protocol UAX9-HL4 (that protocol being recommended for source text starting with Unicode 15.0).
Robin noted that Unicode 15 is due out in September.
I believe at that point in the discussion I specifically mentioned the 13th of September, per https://www.unicode.org/versions/beta-15.0.0.html.

Le sam. 28 mai 2022 à 16:48, Tom Honermann <tom@honermann.net> a écrit :

The summary for the SG16 meeting held May 25th, 2022 is now available.  For those that attended, please review and suggest corrections.

No decisions were made at this meeting.

Tom.