chromium/third_party/blink/web_tests/external/wpt/css/css-text/tab-size/tab-size-inheritance-001.html

<!DOCTYPE html>
<meta charset="utf-8">
<title>CSS Text level 3 Test: tab-size in lengths inherit as absolute lengths</title>
<link rel="author" title="Florian Rivoal" href="https://florian.rivoal.net/">
<link rel="help" href="https://drafts.csswg.org/css-text-3/#tab-size-property">
<link rel="match" href="tab-size-inheritance-001-ref.html">
<meta name="assert" content="tab-size in lengths inherit as absolute lengths">
<style>
.test {
  font-family: monospace;
  font-size: 10px;
  tab-size: 5em;
}
.test div {
  white-space: pre;
  font-size: 20px
}
.test span {
  display: inline-block;
  width: 20px;
  height: 20px;
  background: green;
}
.ref {
  z-index: -1;
  margin-left: 50px;
  position: absolute;
  width: 20px;
  height: 20px;
  background: red;

  /* this is to avoid antialiasing effects at the edge */
  box-sizing: border-box;
  border: 2px solid white;
}
</style>

<p>Test passes if there is a green square and no red.
<div class=ref></div>
<div class=test><div>&#x09;<span></span></div></div>