Firefox-Menü anpassen // Customizing the Firefox menu

[Mira-Bellenbaum]

Concerns the following script:
// Firefox-Menü anpassen

(function () {
setTimeout(function() {
var pane1 = document.getElementById('AMpopup');

// Menüs einfügen 
   var item2 = document.getElementById('AMsettings')
   var fileMenu = document.getElementById('file-menu');
   pane1.insertBefore(fileMenu, item2);
   var editMenu = document.getElementById('edit-menu');
   pane1.insertBefore(editMenu, item2);
   var viewMenu = document.getElementById('view-menu');
   pane1.insertBefore(viewMenu, item2);
   var historyMenu = document.getElementById('history-menu');
   pane1.insertBefore(historyMenu, item2);
   var bookmarksMenu = document.getElementById('bookmarksMenu');
   pane1.insertBefore(bookmarksMenu, item2);
   var toolsMenu = document.getElementById('tools-menu');
   pane1.insertBefore(toolsMenu, item2);
   var helpMenu = document.getElementById('helpMenu');
   pane1.insertBefore(helpMenu, item2);
   var separator = document.createXULElement('menuseparator');
   separator.setAttribute('flex', '1');
   pane1.insertBefore(separator, item2);   
   
// Script-Menüs einfügen
   var UCLmenu = document.getElementById('usercssloader-menu');
      if (UCLmenu)
         pane1.insertBefore(UCLmenu, item2);
         var JSmenu = document.getElementById('ExtraConfigMenu');
      if (JSmenu)
         pane1.insertBefore(JSmenu, item2);
         var EOMbutton = document.getElementById('eom-button');
      if (EOMbutton)
         pane1.insertBefore(EOMbutton, item2.nextSibling);   			 
   }, 3000);   
}) ();   

This script moves the menus from the menu bar to a newly created app menu. All submenus work perfectly, only under "Help" nothing works at all.
Why?
Can you please take a look at this?

The script for creating the app menu works perfectly,
but is from aborix.
If you need that too:
https://www.camp-firefox.de/forum/thema/112673/?postID=1254735#post1254735

That would be so sweet and really great if you could find the error.