+ DEFVAR_LISP ("window-persistent-parameters", Vwindow_persistent_parameters,
+ doc: /* Alist of persistent window parameters.
+This alist specifies which window parameters shall get saved by
+`current-window-configuration' and `window-state-get' and subsequently
+restored to their previous values by `set-window-configuration' and
+`window-state-put'.
+
+The car of each entry of this alist is the symbol specifying the
+parameter. The cdr is one of the following:
+
+nil means the parameter is neither saved by `window-state-get' nor by
+`current-window-configuration'.
+
+t means the parameter is saved by `current-window-configuration' and,
+provided its WRITABLE argument is nil, by `window-state-get'.
+
+The symbol `writable' means the parameter is saved unconditionally by
+both `current-window-configuration' and `window-state-get'. Do not use
+this value for parameters without read syntax (like windows or frames).
+
+Parameters not saved by `current-window-configuration' or
+`window-state-get' are left alone by `set-window-configuration'
+respectively are not installed by `window-state-put'. */);
+ Vwindow_persistent_parameters = list1 (Fcons (Qclone_of, Qt));
+