fixed-position-changed-to-absolute.html

<!DOCTYPE HTML>
<style>
.composited {
  position: absolute;
  will-change: transform;
  width: 150px;
  height: 150px;
  background: #D9CCA7;
}
body {
  background: #402B3C;
}
#layer-A {
  overflow: hidden;
  width: 50px;
  height: 50px;
  border: solid 5px #402B3C;
  position: fixed;
  background: #6AA6A6;
  top: 20px;
  left: 20px;
}
#layer-B {
  width: 100px;
  height: 100px;
  background: #F26835;
  position: absolute;
  top: 100px;
  left: 100px;
}
#layer-C {
  width: 200px;
  height: 20px;
  background: #F2B263;
  position: absolute;
  border: solid 3px #6AA6A6;
  top: 40px;
  left: 40px;
}
</style>
<div class="composited"></div>
<div id="layer-A"></div>
<div id="layer-B"></div>
<div id="layer-C"></div>
<pre><pre>
<script>
if (window.testRunner) {
    testRunner.dumpAsText();
    internals.settings.setPreferCompositingToLCDTextEnabled(true);
} else {
    alert('This test requires testRunner');
}

internals.forceCompositingUpdate(document);
document.getElementById("layer-A").style.position = "absolute";
document.querySelector('pre').textContent = internals.layerTreeAsText(document);
</script>

chromium/third_party/blink/web_tests/compositing/fixed-position-changed-to-absolute.html