context-menu-items.js

loadIntoWindow: function (aDOMWindow) {
    if (!aDOMWindow) return;
    const contentAreaContextMenu = aDOMWindow.document.getElementById('contentAreaContextMenu');
    if (contentAreaContextMenu) {
      const menu = aDOMWindow.document.createElement('menu');
      menu.setAttribute('label', 'Min Vid');
      menu.setAttribute('id', 'myMenu');

      // item one in submenu
      const playMenuItem = aDOMWindow.document.createElement('menuitem');
      playNowMenuItem.setAttribute('label', 'Play Now');
      playNowMenuItem.setAttribute('oncommand', () => {contextMenuLaunch('play_now');});

      // item two in submenu
      const addMenuItem = aDOMWindow.document.createElement('menuitem');
      addMenuItem.setAttribute('label', 'Add to Queue');
      addMenuItem.setAttribute('oncommand', () => {contextMenuLaunch('add');});

      // popup object for containing menuitems
      const menuPopup = aDOMWindow.document.createElement('menu');
      menuPopup.appendChild(playMenuItem);
      menuPopup.appendChild(addMenuItem);

      menu.appendChild(menuPopup);

      console.error('menu ::', menu);
      contentAreaContextMenu.appendChild(menu);
    }
  },