Examples: - Add "Approved:" headers for moderated/closed mailing lists - Add or remove In-Reply-To headers as needed (remove if I reply to an old mail but it

Examples: - Add "Approved:" headers for moderated/closed mailing lists - Add or remove In-Reply-To headers as needed (remove if I reply to an old mail but it has nothing to do with the thread; add if I reply to a mail from a mailing list that I don't have any more but I have the message ID from an archive) - Change the From address.