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Test Info:

<!DOCTYPE html>
<meta charset=utf-8 />
<title>Event Timing: PerformanceObserver with buffered flag and durationThreshold</title>
<script src=/resources/testharness.js></script>
<script src=/resources/testharnessreport.js></script>
<script src=/resources/testdriver.js></script>
<script src=/resources/testdriver-vendor.js></script>
<script src=resources/event-timing-test-utils.js></script>
<div id='myDiv'>Click me</div>
promise_test(async t => {
assert_implements(window.PerformanceEventTiming, 'Event Timing is not supported.');
// Add a PerformanceObserver and observe with a durationThreshold of 30 and buffered flag.
return new Promise(async resolve1 => {
// Add a slow click event and make sure it's dispatched to observers.
await new Promise(async resolve2 => {
// Observer to await until event entry is dispatched.
new PerformanceObserver(() => {
}).observe({type: "event", durationThreshold: 16});
await clickOnElementAndDelay('myDiv', 30);
const afterFirstClick =;
new PerformanceObserver(t.step_func(list => {
const pointerDowns = list.getEntriesByName('pointerdown');
pointerDowns.forEach(entry => {
if (entry.processingStart < afterFirstClick) {
// It is possible that the first event gets a slow duration and hence gets buffered.
// In this case the minDuration must be at least 104, otherwise it shouldn't have been
// buffered.
verifyClickEvent(entry, 'myDiv', true /* isFirst */);
} else {
verifyClickEvent(pointerDowns[0], 'myDiv', false /* isFirst */, 16 /* minDuration*/);
})).observe({type: 'event', durationThreshold: 16, buffered: true});
// This should be the only click observed since the other one would not be buffered.
await clickOnElementAndDelay('myDiv', 30);
}, "PerformanceObserver buffering independent of durationThreshold");