test_bug1515822.html

Enable keyboard shortcuts

<!DOCTYPE HTML>

<html>

<head>

  <title>Test for Bug 1515822 - restore scroll position for display: contents children</title>

  <script src="/tests/SimpleTest/SimpleTest.js"></script>

  <style>

    #shell {

      display: contents;

    #outer {

      width: 200px;

      height: 200px;

      overflow: scroll;

    #inner {

      width: 400px;

      height: 400px;

      background: linear-gradient(to right bottom, white, black);

  </style>

</head>

<body>

<div id="shell">

  <div id="outer">

    <div id="inner">

    </div>

  </div>

</div>

<script>

const outer = document.querySelector('#outer');

outer.scrollTop = 100;

outer.scrollLeft = 100;

document.body.offsetTop; // flush layout

is(outer.scrollTop, 100, 'scroll position should be moved');

is(outer.scrollLeft, 100, 'scroll position should be moved');

outer.parentElement.style.display = 'none';

document.body.offsetTop; // flush layout

is(outer.scrollTop, 0, 'scroll position should be zero');

is(outer.scrollLeft, 0, 'scroll position should be zero');

outer.parentElement.style.display = "";

document.body.offsetTop; // flush layout

is(outer.scrollTop, 100, 'scroll position should be restored');

is(outer.scrollLeft, 100, 'scroll position should be restored');

</script>