<!DOCTYPE html>
<title>Document#fullscreenEnabled setting allowfullscreen after document creation, before response</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<div id="log"></div>
<script>
// Set allowfullscreen attribute in a timeout after <iframe> has been inserted to the document.
// The iframe's response is delayed so it happens after the attribute is set.

async_test((t) => {
  const iframe = document.createElement('iframe');
  // no allowfullscreen attribute

  const path = location.pathname.substring(0, location.pathname.lastIndexOf('/') + 1);
  iframe.src = "http://{{hosts[][]}}:{{ports[http][0]}}" + path + "resources/echo-fullscreenEnabled.html?pipe=trickle(d1)";
  iframe.onload = t.step_func(() => {
    iframe.contentWindow.postMessage('What is document.fullscreenEnabled?', '*');
  });

  window.onmessage = t.step_func_done((e) => {
    assert_false(e.data, 'document.fullscreenEnabled in the iframe');
  });

  document.body.appendChild(iframe);

  t.step_timeout(() => {
    iframe.allowFullscreen = true;
  }, 10);
});
</script>
