iframe sandbox

iframe-sandbox.js

(function (script, callback) {
  var iframe = document.createElement('iframe');
  var blob = new Blob([`<script>(${script.toString()})();</script>`], { 'type': 'text/html' });
  iframe.src = URL.createObjectURL(blob);
  iframe.style.display = 'none';
  iframe.onload = function () {
    typeof callback === 'function' && callback(iframe.contentWindow);
  };
  document.body.appendChild(iframe);
})(
  function () {
    window.r = Math.random();
  },
  function (win) {
    console.log(win.r);
  },
);