<!doctype html>
<meta charset="utf-8">
<title>CSS Test: will-change: backdrop-filter on the root should not generate a containing block for fixed positioned elements.</title>
<link rel="author" title="Philip Rogers" href="mailto:pdr@chromium.org">
<link rel="help" href="https://bugs.chromium.org/p/chromium/issues/detail?id=960953">
<link rel="help" href="https://drafts.csswg.org/css-will-change/#will-change">
<link rel="help" href="https://drafts.fxtf.org/filter-effects-2/#BackdropFilterProperty">
<link rel="match" href="will-change-fixedpos-cb-006-ref.html">
<style>
  html {
    will-change: backdrop-filter;
  }
  body {
    margin: 0;
  }
  .hidden {
    width: 100px;
    height: 100px;
    background: red;
    margin-left: 100px;
    margin-top: 200px;
  }
  .fixedpos {
    position: fixed;
    top: 100px;
    left: 100px;
    background: green;
    height: 100px;
    width: 100px;
  }
  .spacer {
    height: 2000px;
  }
</style>
<!-- This object should be fully hidden by the fixed position object. -->
<div class="hidden"></div>
<div class="fixedpos"></div>
<div class="spacer"></div>
<script>
  window.onload = function() { window.scrollTo(0, 100); };
</script>