access-control-sandboxed-iframe.html

Enable keyboard shortcuts

<!DOCTYPE html>

<html>

  <body>

  <script type="text/javascript">

window.addEventListener("message", (evt) => {

  const url = evt.data;

  const xhr = new XMLHttpRequest;

  xhr.open("GET", url, false);

  try {

    xhr.send();

  } catch(e) {

    parent.postMessage("Exception thrown. Sandboxed iframe XHR access was denied in 'send'.", "*");

    return;

  parent.postMessage(xhr.responseText, "*");

}, false);

parent.postMessage("ready", "*");

  </script>

  </body>

</html>