Teste bitte mal.
Code
		
					
				(function() {
  if (location != 'chrome://browser/content/browser.xul')
    return;
  let tabContextMenu = document.getElementById('tabContextMenu');
  let historyPopup = document.getElementById('goPopup');
  tabContextMenu.addEventListener('popupshowing', function(event) {
    if (event.target != this)
      return;
    // historyPopup.style.visibility = 'collapse';
    historyPopup.showPopup();
    document.getElementById('historyUndoPopup').showPopup();
    let dblHistoryUndoMenu = document.getElementById('historyUndoMenu').cloneNode(true);
    dblHistoryUndoMenu.id = 'context_historyUndoMenu';
    dblHistoryUndoMenu.getElementsByTagName('menupopup')[0].removeAttribute('id');
    tabContextMenu.appendChild(dblHistoryUndoMenu);
  });
  tabContextMenu.addEventListener('popuphiding', function(event) {
    if (event.target != this)
      return;
    tabContextMenu.removeChild(document.getElementById('context_historyUndoMenu'));
    // historyPopup.style.visibility = 'visible';
  });
})();
	
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