Variable: message-use-followup-to
message-use-followup-to is a customizable variable defined in
message.el.gz.
Value
ask
Documentation
Specifies what to do with Followup-To header.
If nil, always ignore the header. If it is t, use its value, but
query before using the "poster" value. If it is the symbol ask,
always query the user whether to use the value. If it is the symbol
use, always use the value.
Source Code
;; Defined in /usr/src/emacs/lisp/gnus/message.el.gz
(defcustom message-use-followup-to 'ask
"Specifies what to do with Followup-To header.
If nil, always ignore the header. If it is t, use its value, but
query before using the \"poster\" value. If it is the symbol `ask',
always query the user whether to use the value. If it is the symbol
`use', always use the value."
:group 'message-interface
:link '(custom-manual "(message)Followup")
:type '(choice (const :tag "ignore" nil)
(const :tag "use & query" t)
(const use)
(const ask)))