Variable: help-xref-stack
help-xref-stack is a buffer-local variable defined in help-mode.el.gz.
Documentation
A stack of ways by which to return to help buffers after following xrefs.
Used by help-follow-symbol and help-xref-go-back.
An element looks like (POSITION FUNCTION ARGS...).
To use the element, do (apply FUNCTION ARGS) then goto the point.
Source Code
;; Defined in /usr/src/emacs/lisp/help-mode.el.gz
(defvar-local help-xref-stack nil
"A stack of ways by which to return to help buffers after following xrefs.
Used by `help-follow-symbol' and `help-xref-go-back'.
An element looks like (POSITION FUNCTION ARGS...).
To use the element, do (apply FUNCTION ARGS) then goto the point.")