third-party-cookie-blocked-on-cross-origin-websocket.https.html

<!DOCTYPE html>
<meta charset="utf-8"/>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/websockets/cookies/support/websocket-cookies-helper.sub.js"></script>

<iframe id="iframe" src=""></iframe>
<script>
if (window.testRunner) {
  // Block third-party cookies.
  testRunner.setBlockThirdPartyCookies(true);
}

async_test(t => {
  window.addEventListener(
      'message',
      t.step_func_done(event => {
        assert_equals(event.data, 'DONE: (none)');
      }),
      false);
  // The iframe is cross-origin from the websocket and from the main frame.
  // The main frame is same-origin as the websocket.
  var url = document.location.href.replace(HTTPS_ORIGIN, HTTPS_CROSS_SITE_ORIGIN)
                                  .replace('third-party-cookie-blocked-on-cross-origin-websocket.https.html', '') +
            'resources/set-cookie.https.html';
  document.getElementById('iframe').setAttribute('src', url);
}, 'Test that first-party cookies are blocked for WebSockets conforming the ' +
    'requirements of the SameSite attribute.');
</script>

chromium/third_party/blink/web_tests/wpt_internal/websocket-cookies/third-party-cookie-blocked-on-cross-origin-websocket.https.html