cyrus-common binary package in Ubuntu Lunar arm64

 Cyrus is an IMAP server designed to handle massive quantities of mail,
 with a number of features not found in other IMAP implementations,
 including support for:
  - running the daemon without root privileges;
  - POP3 and NNTP in addition to plain IMAP;
  - CalDAV and CardDAV;
  - secure IMAP using SSL;
  - server-side filtering with Sieve;
  - mail users without login accounts;
  - simple mail quotas;
  - virtual domains;
  - IPv6.
 .
 Cyrus doesn't support reading from and storing mail in the
 standard mail spool. It stores mail in a separate directory in its
 own MH-like format.
 .
 This package contains the common files needed by the other Cyrus
 components. The cyrus-imapd and/or cyrus-pop3d packages are needed
 to enable IMAP and POP3 support respectively. cyrus-murder can be
 used to enable IMAP, POP3 and LMTP proxying. cyrus-replication
 can be used to provide server replication between two imap servers.

Source package