fullscreen/rendering/backdrop-iframe.html

<!DOCTYPE html>
<html class=reftest-wait>
<title>::backdrop for a fullscreen iframe element</title>
<link rel=match href="backdrop-green-ref.html">
<link rel=help href="https://github.com/w3c/csswg-drafts/issues/6939">
<script src="/resources/testdriver.js"></script>
<script src="/resources/testdriver-vendor.js"></script>

<style>
iframe::backdrop {
  background: green;
}
</style>
<iframe></iframe>
<script>
document.addEventListener('fullscreenchange', () => {
  document.documentElement.classList.remove('reftest-wait');
});
test_driver.bless('fullscreen', () => {
  document.querySelector('iframe').requestFullscreen();
});
</script>