<!DOCTYPE html>
<meta charset="utf-8">
<title>CSS will-change: 'will-change: position' does not create a containing block for fixed positioned elements but does create a containing block for absolutely 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.csswg.org/css-will-change-1/#will-change">
<link rel="match" href="green-square-100-by-100-offset-ref.html">
<meta name="assert" content="If any non-initial value of a property would cause the element to generate a containing block for fixed-position elements, specifying that property in will-change must cause the element to generate a containing block for fixed-position elements.">
<style>
html, body { margin: 0; padding: 0; }
div { width: 100px; height: 100px }
#wc { will-change: position; margin: 100px 0 0 100px; background: red }
.child { width: 50px; background: green }
#fixpos { position: fixed; top: 100px; left: 100px }
#abspos { position: absolute; top: 0; left: 50px }
</style>
<body>
<div id="wc">
<div class="child" id="fixpos">
</div>
<div class="child" id="abspos">
</div>
</div>
</body>
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