Severity: minor

Hi Philip,

Nice job on the v3 stuff. I happened across a couple capabilities being
requested that don't officially exist, a distinction you've probably
picked up on in the course of pursuing this work [1]. The couple that
slipped by are always NAK'd but basically harmless, so you may just want
to leave 'em or otherwise go your own way. If so, please ignore this.

Thanks,
J.P.

P.S. The CTCP "KEEPALIVE" in the ergo session below jumped out at me;
just FYI in case that's of any interest.


[1] For others who may be wondering, the specs are still a bit rough
    when it comes to denoting with any consistency when an extension has
    a corresponding ("requestable") capability. For example, some
    extensions (like STS) have caps that are strictly server-only,
    meaning you, a client, shouldn't REQ them. Other caps are only
    effectively server-only, meaning it doesn't matter if you REQ them
    or not (negated or otherwise). And some extensions (like the two in
    this bug) don't offer caps at all. This has confused me enough over
    the years that I've taken to looking to other clients as well as WG
    chatter on Github for clues, which can get old pretty fast.


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