chromium/third_party/blink/web_tests/external/wpt/html/browsers/history/the-history-interface/non-automated/traverse_the_history_unload_prompt_1-manual.html

<!doctype html>
<title>Traversing the history, prompt in before unload, navigation denied</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<div id="log"></div>
<script>
  setup({timeout:3600000});
  var t = async_test();
  started = false;
  pages = []
  timer = null;
  beforeunload_ran = false;
  start_test_wait = t.step_func(
    function() {
      clearTimeout(timer);
      timer = setTimeout(t.step_func(
        function() {
          try {
            assert_true(beforeunload_ran, "beforeunload event handler ran");
            assert_array_equals(pages, [2], "Pages opened during history navigation");
            t.done();
          } finally {
            win.close();
          }
        }
      ), 500);
    }
  );
  t.step(function() {win = window.open("history_entry.html?urls=traverse_the_history_unload_prompt_1-1.html");
});
</script>