(focus-follows-mouse): Document that it doesn't have any effect on MS-Windows.

diff --git a/lisp/frame.el b/lisp/frame.el
index d041da254f5204ef9dc64455250d0d9a70d0b7a4..a92fa3c8133e214ec0b96d65c8de6aebda5d8063 100644 (file)
--- a/lisp/frame.el
+++ b/lisp/frame.el
@@ -685,7 +685,9 @@ the user during startup."
   "*Non-nil if window system changes focus when you move the mouse.
 You should set this variable to tell Emacs how your window manager
 handles focus, since there is no way in general for Emacs to find out
-automatically."
+automatically.
+
+This variable does not have any effect on MS-Windows."
   :type 'boolean
   :group 'frames
   :version "20.3")