css/css-position/position-absolute-container-dynamic-002.html

<!DOCTYPE html>
<title>CSS Position Absolute: dynamic changes to containing block height</title>
<link rel="author" href="mailto:atotic@google.com">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<link rel="help" href="https://bugs.chromium.org/p/chromium/issues/detail?id=933054">
<meta name="assert" content="Chrome regression: abspos descendant responds to containing block size change through line items">
<style>

#container {
  position: relative;
}
#intermediate {
  overflow: hidden;
  width:200px;
  height:200px;
  background:red;
}
#block {
  height:200px;
  background:green;
}
#target {
  position: absolute;
  width: 200px;
  height: 100px;
  background:green;
}
</style>
<!-- Test for crbug.com/933054
  Relayout optimizations cause OOF descendant not to be
  repositioned
-->
<div id="container">
  <div id="intermediate">
    <div id="block"></div>
    <div id="target"></div>
  </div>
</div>

<script>
document.body.offsetTop;
test(() => {
  document.getElementById("block").style.height = "100px";
  assert_equals(document.querySelector("#target").offsetTop, 100);
}, '#target static position responded to parent relayout');
</script>