"When using the SASL SCRAM mechanism, the SCRAM-SHA-256-PLUS variant SHOULD be preferred over the SCRAM-SHA-256 variant, and SHA-256 variants [RFC7677] SHOULD be preferred over SHA-1 variants [RFC5802]".
There is only SCRAM-SHA-1, there is not SCRAM-SHA-1-PLUS:
"When using the SASL SCRAM mechanism, the SCRAM-SHA-256-PLUS variant SHOULD be preferred over the SCRAM-SHA-256 variant, and SHA-256 variants [RFC7677] SHOULD be preferred over SHA-1 variants [RFC5802]".
There is only SCRAM-SHA-1, there is not SCRAM-SHA-1-PLUS:
There is not SCRAM-SHA-256(-PLUS):
I add SCRAM-SHA-512(-PLUS): https://xmpp.org/extensions/inbox/hash-recommendations.html
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