chromium/third_party/blink/web_tests/external/wpt/html/links/manifest/document-not-attached-manual.html

<!DOCTYPE html>
<title>
  Manifest attached to document without a browsing context
</title>
<link rel="help" href="https://html.spec.whatwg.org/#link-type-manifest" />
<script>
  // Create an orphan document, and make sure it doesn't get used
  const doc = document.implementation.createHTMLDocument("Orphan document");
  const link = doc.createElement("link");
  link.rel = "manifest";
  link.href = "/appmanifest/name-member/name-member-fail.webmanifest";
  doc.head.append(link);
</script>
<h1>Manifest attached to document that does not have a browsing context</h1>
<p>
  To pass, the user agent must not use the manifest in the unattached document.
</p>