ansible-role-mailserver/templates/dovecot/conf.d/15-mailboxes.conf

namespace inbox {
  mailbox Drafts {
    auto = subscribe
    special_use = \Drafts
  }
  mailbox Junk {
    auto = subscribe
    special_use = \Junk
  }
  mailbox Trash {
    auto = subscribe
    special_use = \Trash
  }
  mailbox Sent {
    auto = subscribe
    special_use = \Sent
  }
}