Currently the IMAP ID command response is a hardcoded literal in crates/imap/src/op/capability.rs (handle_id), always returning:
* ID ("name" "Stalwart" "version" "1.0.0" "vendor" "Stalwart Labs LLC" "support-url" "https://stalw.art")
This discloses product identity unconditionally to any connection, including pre-authentication/anonymous sessions. It can be also disclosed via CAPABILITIES response.
SMTP already has smtpGreeting, letting operators suppress banner/version disclosure on that protocol. It would be great to have the equivalent for IMAP — something like an imap.id setting (e.g. enable: false to respond with ID NIL, or override fields to return custom name/version/vendor values) mirroring the existing Imap config object fields.