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content / test / data / performance_timeline / lcp-start-time-precision.html [blame]
<!DOCTYPE HTML>
<meta charset=utf-8>
<title>Largest Contentful Paint Start Time Precision.
</title>
<body>
<script>
const getLCPStartTime = async () => {
return await new Promise(resolve => {
new PerformanceObserver((entryList, observer) => {
resolve(entryList.getEntries()[0].startTime);
observer.disconnect();
}).observe({ type: 'largest-contentful-paint', buffered: true });
});
}
const getFCPStartTime = () => {
return performance.getEntriesByName('first-contentful-paint')[0].startTime;
}
const isEqualToPrecision = async (n) => {
let lcpStartTime = await getLCPStartTime();
let fcpStartTime = getFCPStartTime();
return lcpStartTime.toPrecision(n) == fcpStartTime.toPrecision(n);
}
</script>
<img src='../single_face.jpg' id="test" />
</body>