<!DOCTYPE html>
<title>Sticky positioning can cause overflow but must be accessible.</title>
<link rel="help" href="https://www.w3.org/TR/css-position-3/#sticky-pos" />
<meta name="assert" content="This test checks that a sticky positioned element
does not extend overflow" />

<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>

<style>
.container {
  overflow-y: scroll;
  width: 100px;
  height: 100px;
}

.box {
  background-color: green;
  height: 50px