Source code

Revision control

Copy as Markdown

Other Tools

Test Info:

<meta charset=utf-8>
<title>Largest Contentful Paint: contracted image bounded by display size.</title>
<style type="text/css">
#image_id {
width: 50px;
height: 50px;
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="resources/largest-contentful-paint-helpers.js"></script>
async_test(function (t) {
assert_implements(window.LargestContentfulPaint, "LargestContentfulPaint is not implemented");
const beforeLoad =;
const observer = new PerformanceObserver(
t.step_func_done(function(entryList) {
assert_equals(entryList.getEntries().length, 1);
const entry = entryList.getEntries()[0];
const url = window.location.origin + '/images/black-rectangle.png';
// black-rectangle.png is 100 x 50. It occupies 50 x 50 so size will be bounded by the displayed size.
const size = 50 * 50;
checkImage(entry, url, 'image_id', size, beforeLoad);
observer.observe({type: 'largest-contentful-paint', buffered: true});
}, 'Largest Contentful Paint: |size| attribute is bounded by display size.');
<img src='/images/black-rectangle.png' id='image_id'/>