Index: /trunk/src/org/openstreetmap/josm/gui/help/HelpBrowser.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/gui/help/HelpBrowser.java	(revision 6799)
+++ /trunk/src/org/openstreetmap/josm/gui/help/HelpBrowser.java	(revision 6800)
@@ -217,10 +217,12 @@
             new WindowGeometry(this).remember(getClass().getName() + ".geometry");
         }
-        if(windowMenuItem != null && !visible) {
-            Main.main.menu.windowMenu.remove(windowMenuItem);
-            windowMenuItem = null;
-        }
-        if(windowMenuItem == null && visible) {
-            windowMenuItem = MainMenu.add(Main.main.menu.windowMenu, focusAction, MainMenu.WINDOW_MENU_GROUP.VOLATILE);
+        if (Main.main != null && Main.main.menu != null && Main.main.menu.windowMenu != null) {
+            if(windowMenuItem != null && !visible) {
+                Main.main.menu.windowMenu.remove(windowMenuItem);
+                windowMenuItem = null;
+            }
+            if(windowMenuItem == null && visible) {
+                windowMenuItem = MainMenu.add(Main.main.menu.windowMenu, focusAction, MainMenu.WINDOW_MENU_GROUP.VOLATILE);
+            }
         }
         super.setVisible(visible);