navigation-api/navigate-event/navigate-form-reload.html

<!doctype html>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<iframe id="iframe" name="i" src="/common/blank.html"></iframe>
<form id="form" action="/common/blank.html?1" method="post" target="i"></form>
<script>
async_test(t => {
  window.onload = t.step_func(() => {
    navigation.onnavigate = t.step_func_done(() => {
      assert_unreached("onnavigate should not have fired in source window");
    });
    iframe.contentWindow.navigation.onnavigate = t.step_func(e => {
      assert_equals(e.navigationType, "push");
      assert_not_equals(e.formData, null);

      iframe.onload = t.step_func(() => {
        iframe.contentWindow.navigation.onnavigate = t.step_func_done(e => {
          assert_equals(e.navigationType, "reload");
          assert_equals(e.formData, null);
        });

        iframe.contentWindow.location.reload();
      });
    });
    form.submit();
  });
}, "reloading a page created from form submission results in formData of null, not the original form data");
</script>