<!DOCTYPE html>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="resources/context-helper.js"></script>
<script>
window.scriptToRun =
    'relevantWindow.open("target.html", "target");';

async_test(t => {
  window.addEventListener("message", t.step_func_done(function(e) {
    // Base URL used for parsing a relative URL to `target.html`
    // should be the base URL of the entry settings object in
    // https://html.spec.whatwg.org/C/#wi