Mail Headers
message-required-mail-headers
See News Headers, for the syntax of this variable. It is (From Subject Date (optional . In-Reply-To) Message-ID (optional . User-Agent)) by default.
message-ignored-mail-headers
Regexp of headers to be removed before mailing. The default is
‘^[GF]cc:\\|^Resent-FCC:\\|^Xref:\\|^X-Draft-From:\\| ^X-Gnus-Agent-Meta-Information:’.
message-default-mail-headers
This string is inserted at the end of the headers in all message buffers that are initialized as mail.
message-generate-hashcash
Variable that indicates whether ‘X-Hashcash’ headers should be computed for the message. See Hashcash in The Gnus Manual. If opportunistic, only generate the headers when it doesn’t lead to the user having to wait.