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<!DOCTYPE HTML>
<meta charset=utf-8>
<title>Container Timing: observe after painting happened without buffering</title>
<body>
<style>
body {
margin: 0;
}
</style>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/container-timing/resources/container-timing-helpers.js"></script>
<script src="/element-timing/resources/element-timing-helpers.js"></script>
<script>
let beforeRender;
async_test(function (t) {
assert_implements(window.PerformanceContainerTiming, "PerformanceContainerTiming is not implemented");
t.step_timeout(() => {
const observer = new PerformanceObserver(
t.step_func_done(function(entryList) {
assert_unreached("Painting happened before observing, it should not create a containertiming entry");
})
);
observer.observe({type: 'container', buffered: false });
t.step_timeout(() => {
t.done();
}, 2000);
}, 2000);
// Add the image during onload to be sure that the observer is registered
// in time.
window.onload = () => {
// Add image of width equal to 100 and height equal to 100.
const img = document.createElement('img');
img.src = '/container-timing/resources/square100.png';
img.setAttribute('containertiming', 'image_ct');
img.setAttribute('id', 'my_id');
document.body.appendChild(img);
beforeRender = performance.now();
};
}, 'containertiming does not report paints before observing if buffering is disabled.');
</script>
</body>