Variable: gnus-use-cross-reference
gnus-use-cross-reference is a customizable variable defined in
gnus.el.gz.
Value
t
Documentation
Non-nil means that cross referenced articles will be marked as read.
If nil, ignore cross references. If t, mark articles as read in subscribed newsgroups. If neither t nor nil, mark as read in all newsgroups.
Source Code
;; Defined in /usr/src/emacs/lisp/gnus/gnus.el.gz
(defcustom gnus-use-cross-reference t
"Non-nil means that cross referenced articles will be marked as read.
If nil, ignore cross references. If t, mark articles as read in
subscribed newsgroups. If neither t nor nil, mark as read in all
newsgroups."
:group 'gnus-server
:type '(choice (const :tag "off" nil)
(const :tag "subscribed" t)
(sexp :format "all"
:value always)))