A JavaScript insert that is used on the offical Kahoot website.
Go to kahoot and type "javascript:" without the quotes into the search bar of the kahoot tab. After you finished typing, paste the following code after the text you just typed. Press enter and watch the magic happen.
(function()%7B document.title = "Close this to stop"%3B document.body.innerHTML = '<div style="display:flex%3Bjustify-content:center%3Balign-items:center%3Bheight:100%%3B"><p style="font-size:3em%3Btext-align:center%3B">Close when done finding pin</p></div>'%3B var interval = setInterval(function() { var code = Math.floor(Math.random() * 9000000 + 1000000)%3B var url = "https://kahoot.it/?pin=" + code + "&refer_method=link"%3B var win = window.open(url, "_blank")%3B setTimeout(function() { if (win.document.querySelector('div[data-functional-selector="notification-bar-error"]')) { win.close()%3B } }, 600)%3B }, 600)%3B %7D)()%3B