Public bug reported:
From RFC 2369:
The List-Post field describes the method for posting to the list. This is typically the address of the list, but MAY be a moderator, or potentially some other form of submission. For the special case of a list that does not allow posting (e.g., an announcements list), the List-Post field may contain the special value "NO".
Mailman currently prevents adding the List-Post header for announce-only lists. Instead it should include it with the value of NO.
** Affects: mailman Importance: High Status: Confirmed
** Tags: easy mailman3
** Changed in: mailman Status: Confirmed => Fix Committed
** Changed in: mailman Status: Fix Committed => Fix Released