rem: var navTB = document.getElementById("nav-bar"); navTB.parentNode.appendChild(printPreviewTB); 
add: var navToolbox = document.getElementById("navigator-toolbox"); navToolbox.parentNode.insertBefore(printPreviewTB, navToolbox); 
context: function showPrintPreviewToolbar(){  toggleAffectedChrome(true);  const kXULNS =     "http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul";  var printPreviewTB = document.createElementNS(kXULNS, "toolbar");  printPreviewTB.setAttribute("printpreview", true);  printPreviewTB.setAttribute("id", "print-preview-toolbar");  var navTB = document.getElementById("nav-bar");  navTB.parentNode.appendChild(printPreviewTB);}
meta: 5872	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/5872/f72ade79d369135e6061d25e1d21efac093a283c/browser.js/buggy/xpfe/browser/resources/content/browser.js