5322 => 'Internet message format (2008)',
3501 => 'IMAP4rev1',
2177 => 'IMAP IDLE',
+ 2683 => 'IMAP4 Implementation Recommendations',
# 5032 = 'WITHIN search extension for IMAP',
4978 => 'IMAP COMPRESS Extension',
# 5182 = 'IMAP Extension for Referencing the Last SEARCH Result',
Other relevant documentation
----------------------------
+* IMAP capabilities registry and response codes:
+ https://www.iana.org/assignments/imap-capabilities
+ https://www.iana.org/assignments/imap-response-codes
+
* Documentation/technical/http-protocol.txt in git source code:
https://public-inbox.org/git/9c5b6f0fac/s