diff --git a/hw/xquartz/X11Application.m b/hw/xquartz/X11Application.m
index 2efbd65..a9ee693 100644
--- a/hw/xquartz/X11Application.m
+++ b/hw/xquartz/X11Application.m
@@ -1240,7 +1240,7 @@ X11ApplicationMain(int argc, char **argv, char **envp)
 
     /* Calculate the height of the menubar so we can avoid it. */
     aquaMenuBarHeight = NSHeight([[NSScreen mainScreen] frame]) -
-                        NSMaxY([[NSScreen mainScreen] visibleFrame]);
+                        NSHeight([[NSScreen mainScreen] visibleFrame]);
 
 #ifdef HAVE_LIBDISPATCH
     eventTranslationQueue = dispatch_queue_create(