no-manifest-from-iframe-manual.html

<!DOCTYPE html>
<title>
  Don't install manifests that are not top-level from browsing contexts
</title>
<link rel="help" href="https://html.spec.whatwg.org/#link-type-manifest" />
<h1>Don't install manifests that are not top-level from browsing contexts</h1>
<p>
  To pass, the user agent must not use the manifest in iframe. The user agent
  must behave as if there is no manifest present.
</p>
<script>
  const iframe = document.createElement("iframe");
  iframe.srcdoc = "<h1>hi</h1>";
  document.body.append(iframe);
  iframe.onload = () => {
    const link = iframe.contentDocument.createElement("link");
    link.rel = "manifest";
    link.href = "/appmanifest/name-member/name-member-fail.webmanifest";
    iframe.contentDocument.head.append(link);
  };
</script>

chromium/third_party/blink/web_tests/external/wpt/html/links/manifest/no-manifest-from-iframe-manual.html