* doc/lispref/help.texi (Keys in Documentation):
* etc/NEWS: Document why text-quoting-style is not a
customizable variable (Bug#23372).
before Emacs version 25. The default value @code{nil}
acts like @code{curve} if curved single quotes are displayable, and
like @code{grave} otherwise.
+
+This variable can be used by experts on platforms that have problems
+with curved quotes. As it is not intended for casual use, it is not a
+user option.
@end defvar
@defun substitute-command-keys string
apostrophes, and to 'grave' for grave accent and apostrophe. The
default value nil acts like 'curve' if curved single quotes are
displayable, and like 'grave' otherwise. The new variable affects
-display of diagnostics and help, but not of info.
+display of diagnostics and help, but not of info. As the variable is
+not intended for casual use, it is not a user option.
+++
** substitute-command-keys now replaces quotes.