fix display direction of context sub-menu

packages/node_modules/@node-red/editor-client/src/js/ui/contextMenu.js

@@ -152,8 +152,16 @@ RED.contextMenu = (function() {
             }
 
         }
+
+        var direction = "right";
+        var MENU_WIDTH = 600; // can not use menu width here
+        if ((options.x -$(document).scrollLeft()) >
+            ($(window).height() -MENU_WIDTH)) {
+            direction = "left";
+        }
+        
         menu = RED.menu.init({
-            direction: 'right',
+            direction: direction,
             onpreselect: function() {
                 disposeMenu()
             },