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Test Info: Warnings

<!doctype html>
<meta charset=utf-8>
<title>Largest Contentful Paint: observe element with css generated image</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="resources/largest-contentful-paint-helpers.js"></script>
<style>
#target {
content: url('/images/lcp-256x256.png');
}
</style>
<body>
<script>
setup({"hide_test_state": true});
async_test(function (t) {
assert_implements(window.LargestContentfulPaint, "LargestContentfulPaint is not implemented");
const beforeLoad = performance.now();
const observer = new PerformanceObserver(
t.step_func_done(function(entryList) {
const entries = entryList.getEntries();
assert_equals(entries.length, 1);
const url = window.location.origin + '/images/lcp-256x256.png';
checkImage(entries[0], url, 'target', 65536, beforeLoad);
}));
observer.observe({entryTypes: ['largest-contentful-paint']});
}, 'Largest Contentful Paint: CSS generated image is observable.');
</script>
<div id="target"></div>
</body>