<!DOCTYPE html>
<meta charset="utf-8">
<title>CSS filters: Creating containing block for fixed positioned elements</title>
<link rel="author" title="L. David Baron" href="https://dbaron.org/">
<link rel="author" title="Mozilla" href="http://www.mozilla.org/">
<link rel="help" href="https://drafts.fxtf.org/filters-1/#FilterProperty">
<link rel="help" href="http://www.w3.org/2015/02/10-fx-minutes.html#action02">
<link rel="match" href="filter-cb-dynamic-1-ref.html">
<meta name="flags" content="dom">
<style>
html, body { margin: 0; padding: 0 }
#changefilter {
position: absolute;
top: 100px;
left: 100px;
}
#abscovered {
position: absolute;
top: 50px;
left: 50px;
background: red;
height: 100px;
width: 100px;
}
#fixedmoves {
position: fixed;
top: 150px;
left: 150px;
background: green;
height: 100px;
width: 100px;
}
</style>
<body>
<div id="changefilter" style="filter: blur(4px)">
<div id="abscovered"></div>
<div id="fixedmoves"></div>
</div>
<script>
var changefilter = document.getElementById("changefilter");
var fixedmoves = document.getElementById("fixedmoves");
var causeFlush = fixedmoves.offsetTop;
changefilter.style.filter = "";
</script>
</body>