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Test Info: Warnings
- This test has a WPT meta file that expects 1 subtest issues.
- This WPT test may be referenced by the following Test IDs:
- /largest-contentful-paint/animated/observe-animated-image-webp.tentative.html - WPT Dashboard Interop Dashboard
<!DOCTYPE HTML>
<html>
<head>
<meta charset=utf-8>
<title>Largest Contentful Paint: observe image.</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="../resources/largest-contentful-paint-helpers.js"></script>
</head>
<body>
<script>
promise_test(async () => {
assert_implements(window.LargestContentfulPaint,
"LargestContentfulPaint is not implemented");
const beforeLoad = performance.now();
// 142 is the size of the animated WebP up until the first frame.
// The trickle pipe delays the response after the first frame by 1 second.
const url = window.location.origin +
`/images/webp-animated.webp?pipe=trickle(142:d${delay_pipe_value})`;
const entry = await load_and_observe(url);
// webp-animated.webp is 11 by 29.
const size = 11 * 29;
checkImage(entry, url, 'image_id', size, beforeLoad, ["animated"]);
}, "Same origin animated image is observable and has a first frame.");
</script>
</body>
</html>