--- Utils.java	2016-12-09 16:10:01.660349512 +0200
+++ Utils-new.java	2016-12-09 15:47:52.157662974 +0200
@@ -466,7 +466,7 @@
 
         if (orientation == NodeOrientation.RIGHT_TO_LEFT && hpos == HPos.CENTER) {
             //TODO - testing for an instance of Stage seems wrong but works for menus
-            if (scene.getWindow() instanceof Stage) {
+            if (scene.getWindow() instanceof Window) {
                 layoutX = layoutX + parentBounds.getWidth() - anchorWidth;
             } else {
                 layoutX = layoutX - parentBounds.getWidth() - anchorWidth;