Unclear how servers should send cap updates

[emersion]

Is this valid if a server looses the ability to perform SASL EXTERNAL auth?

CAP NEW sasl=PLAIN,EXTERNAL
[…]
CAP NEW sasl=PLAIN

Or should the server send a CAP DEL sasl in-between? The latter would have some annoying consequences, e.g. the client will need to CAP REQ sasl again, even though the server never lost the ability to perform SASL PLAIN auth.

[slingamn]

I don't know that those consequences are necessarily true, but it seems to me that this is just a new value of the sasl CAP, and the server should be able to push it out to clients using CAP NEW without the need for CAP DEL. The spec does say this (in the context of CAP LS, not cap-notify, but the analogy seems clear):

If a capability with values is sent multiple times, the last one received takes priority.

[emersion]

Oh, I missed it, thanks. Yes, I think that makes the most sense as well. I'll send a PR to disambiguate if you don't mind?