select-willvalidate-readonly-attribute.html

<!DOCTYPE HTML>
<meta charset="utf-8">
<title>Select element with "readonly" attribute shouldn't be barred from constraint validation</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>

<select id="singleSelect" readonly>
  <option>1
  <option>2
</select>

<select id="multiSelect" readonly multiple>
  <option>a
  <option>b
  <option>c
  <option>d
</select>

<script>
  test(() => {
    assert_true(singleSelect.willValidate);
    assert_true(multiSelect.willValidate);
  });
</script>

chromium/third_party/blink/web_tests/external/wpt/html/semantics/forms/the-select-element/select-willvalidate-readonly-attribute.html