chromium/third_party/blink/web_tests/external/wpt/css/css-transforms/individual-transform/stacking-context-ref.html

<!DOCTYPE html>
<html>
  <head>
    <title>
      Reference: Individual transform properties' animations create stacking context in delay phase
    </title>
    <style>
      #back {
        height: 100px;
        width: 100px;
        position: fixed;
        background: green;
        margin-top: 50px;
      }
      #test {
        width: 100px;
        height: 100px;
        background: blue;
        will-change: transform;
      }
    </style>
  </head>
  <body>
    <div id="back"></div>
    <div id="test"></div>
  </body>
</html>