chromium/third_party/blink/web_tests/external/wpt/css/css-conditional/at-supports-selector-webkit-slider-thumb.tentative.html

<!doctype html>
<title>CSS Test (Conditional Rules): In @supports, known -webkit- pseudo elements can be parsed successfully</title>
<link rel="help" href="https://drafts.csswg.org/css-conditional-3/#at-supports">
<link rel="match" href="at-supports-001-ref.html">
<style>
  div {
    background:red;
    height:100px;
    width:100px;
  }
  /* This matches in user agents supporting ::-webkit-slider-thumb. */
  @supports selector(input::-webkit-slider-thumb) {
    div { background-color:green; }
  }
  /* This should never match. */
  @supports selector(input::-webkit-asdf) {
    div { background-color:red; }
  }
</style>
<p>Test passes if there is a <strong>filled green square</strong> and <strong>no red</strong>.</p>
<div></div>