#1234: Some header fields cannot be edited. Comment (by pdmef):
For the record, the References: issue can be partially worked around with by In-Reply-To (partially because it won't prevent writing References:, but for messages without any thread info it works). The Sender: header works with recent version, too. Since besides sender and recipient Date: is the only required header field for RfC2822, it's not purely informational and thus it makes sense to have an accurate one (which may be important for postponed messages, too). -- Ticket URL: <http://dev.mutt.org/trac/ticket/1234#comment:10>
