Well hello This is a first blog post here. Probably I will post something here sometimes. Meanwhile, here's a tiny snippet for you: (ifr => { document.body.appendChild(ifr); const newKeys = {}; Object.entries(window).forEach(([key, value]) => { if (!ifr.contentWindow.hasOwnProperty(key)) { var type = typeof value; newKeys[type] = newKeys[type] || {}; newKeys[type][key] = value; } }); ifr.parentNode.removeChild(ifr); return newKeys; })(document.createElement("iframe")); It will find all the unusual global variables for the page.