chromium/third_party/blink/web_tests/external/wpt/html/browsers/browsing-the-web/back-forward-cache/eligibility/shared-worker.html

<!doctype html>
<meta name="timeout" content="long">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/common/utils.js"></script>
<script src="/common/dispatcher/dispatcher.js"></script>
<script src="../resources/helper.sub.js"></script>
<script>
// Check whether the page is BFCached when there are shared workers that are
// already loaded.
runBfcacheTest({
  funcBeforeNavigation: async () => {
    globalThis.worker = new SharedWorker('../resources/echo-worker.js');
    // Make sure the worker starts before navigation.
    await WorkerHelper.pingWorker(globalThis.worker);
  },
  funcAfterAssertion: async (pageA) => {
    // Confirm that the worker is still there.
    assert_equals(
      await pageA.execute_script(() => WorkerHelper.pingWorker(globalThis.worker)),
      'PASS',
      'SharedWorker should still work after restored from BFCache');
  }
}, 'Eligibility: shared workers');
</script>