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<meta charset="utf8">
<title>CSS Content Visibility: Contentvisibilityautostatechange fires once when c-v auto's dialog ancestor show</title>
<link rel="author" title="Cathie Chen" href="mailto:[email protected]">
<link rel="help" href="https://drafts.csswg.org/css-contain/#content-visibility">
<meta name="assert" content="Contentvisibilityautostatechange fires once when c-v auto's dialog ancestor show">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/common/rendering-utils.js"></script>
<style>
#inner {
content-visibility: auto;
contain-intrinsic-size: 100px 100px;
}
</style>
<dialog id="dialog">
<div id="inner">
<div style="height: 200px; width: 200px;">content</div>
</div>
<div id="spacer" style="height: 100000px;"></div>
</dialog>
<script>
promise_test(async () => {
let count = 0;
inner.addEventListener("contentvisibilityautostatechange", (e) => {
count++;
});
dialog.show();
// getBoundingClientRect shouldn't trigger "contentvisibilityautostatechange", because the proximity to the viewport is not determined now.
inner.getBoundingClientRect().height;
// It takes at least one frame to determine the proximity to the viewport.
await waitForAtLeastOneFrame();
// getBoundingClientRect should trigger "contentvisibilityautostatechange" now.
inner.getBoundingClientRect().height;
await waitForAtLeastOneFrame();
assert_equals(count, 1);
dialog.close();
}, "Contentvisibilityautostatechange fires once when c-v auto's dialog ancestor show()");
</script>
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