FAQ says "Implement a meaningful subset of IMAP for access to local storage."
What subset do you implement? Thanks.
Currently it is base IMAP4rev1 specification (RFC 3501) minus /Recent flag plus SASL-IR, APPENDLIMIT, MOVE, CHILDREN, SPECIAL-USE, COMPRESS, UNSELECT and IDLE extensions. Support for CONDSTORE and UIDPLUS extensions is planned.