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Test Info: Warnings

  • This test gets skipped with pattern: toolkit == 'android'
<!doctype html>
<title>Test for bug 1526609</title>
<script src="/tests/SimpleTest/SimpleTest.js"></script>
<script src="/tests/SimpleTest/EventUtils.js"></script>
body {
margin: 0;
.scroller {
overflow-y: auto;
position: relative;
width: 500px;
height: 300px;
.kid {
position: absolute;
width: 100%;
background: linear-gradient(to bottom, red, green);
line-height: 100px;
<div class="scroller" id="scroller">
<div class="kid"></div>
let text = " foo bar ";
for (let i = 0; i < 16; ++i)
text = text + text;
document.querySelector(".kid").innerText = text;
const scroller = document.querySelector("#scroller");
is(scroller.scrollTop, 0, "Initial scroll position");
ok(scroller.scrollTopMax > 0, "Should be able to scroll down");
scroller.scrollTop = scroller.scrollTopMax;
is(scroller.scrollTop, scroller.scrollTopMax, "Should've scrolled");
const origWidth = scroller.offsetWidth;
const utils = SpecialPowers.DOMWindowUtils;
// Take control of the refresh driver
// Force the next reflow to get interrupted
utils.forceReflowInterrupt(); = "300px";
isnot(scroller.scrollTop, 0, "Shouldn't have lost scroll position");
isnot(scroller.offsetWidth, origWidth, "Should've had to reflow");