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Test Info: Warnings

<meta charset=utf-8>
<title>Largest Contentful Paint: size when image overflows</title>
<!-- In this test, an image with an intrinsic size of 100 x 50 is added, but
scaled up in order to overflow the viewport. It should not be reported. -->
body {
margin: 0px;
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="resources/largest-contentful-paint-helpers.js"></script>
const viewportWidth = document.documentElement.clientWidth;
const viewportHeight = document.documentElement.clientHeight;
setup({"hide_test_state": true});
async_test(function (t) {
assert_implements(window.LargestContentfulPaint, "LargestContentfulPaint is not implemented");
const beforeLoad =;
new PerformanceObserver(
t.step_func_done(function(entryList) {
assert_equals(entryList.getEntries().length, 1, 'Should have received only one entry!');
const entry = entryList.getEntries()[0];
if (entry.url)
assert_unreached('Should not have received an image entry!');
).observe({type: 'largest-contentful-paint', buffered: true});
// Add an image, setting width and height equal to viewport.
img = document.createElement('img');
img.src = '/images/green-100x50.png'; = 'image_id';
img.width = viewportWidth * 2;
img.height = viewportHeight * 2;
img.onload = () => {
const p = document.createElement('p');
p.innerHTML = 'a'; = 'position: absolute; top: 10px; left: 10px;';
}, 'The intersectionRect of an img element overflowing is computed correctly');