<!doctype html>
<title>CSS Test: Dynamic change to the block size inside an auto-sized flex item</title>
<link rel="author" title="Emilio Cobos Álvarez" href="mailto:emilio@crisal.io">
<link rel="author" title="Mozilla" href="https://mozilla.org">
<link rel="help" href="https://drafts.csswg.org/css-flexbox">
<link rel="help" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1496833">
<link rel="match" href="dynamic-bsize-change-ref.html">
<style>
  div {
    border: 1px solid;
  }
  #myHeightChanges {
    width: 100px;
    height: 100px;
    background: green;
  }
</style>
<div style="display:flex; flex-direction:column">
  <div style="height:auto">
    <div id="myHeightChanges"></div>
  </div>
</div>
<script>
onload = function() {
  window.unused = myHeightChanges.offsetTop;
  myHeightChanges.style.height = "200px";
}
</script>