chromium/third_party/blink/web_tests/fast/ruby/line-height.html

<!DOCTYPE html>
<meta charset="utf-8">
<body>
<script src="../../resources/testharness.js"></script>
<script src="../../resources/testharnessreport.js"></script>

<style>
.para {
  line-height: 1;
  font-family: 'Osaka', 'Noto Sans CJK JP';
  font-size: 40px;
  padding: 0px;
}
</style>

<p id="p1" class="para">
諸行<br>
無常の<br>
<ruby>響きあり</ruby>
</p>

<p id="p2" class="para">
諸行<br>
無常の<br>
響きあり
</p>

<script>
test(() => {
  const p1 = document.querySelector('#p1');
  const p2 = document.querySelector('#p2');
  assert_equals(p1.offsetHeight, p2.offsetHeight);
}, 'RUBY without RT should not affect line height');
</script>
</body>