chromium/third_party/blink/web_tests/external/wpt/css/css-view-transitions/new-content-is-empty-div.html

<!DOCTYPE html>
<html class=reftest-wait>
<title>View transitions: old content captures an empty div</title>
<link rel="help" href="https://drafts.csswg.org/css-view-transitions-1/">
<link rel="author" href="mailto:[email protected]">
<link rel="match" href="new-content-is-empty-div-ref.html">

<script src="/common/reftest-wait.js"></script>
<style>
div {
  contain: paint;
  width: 100px;
  height: 100px;
  position: absolute;
  top: 50px;
}
#source {
  left: 50px;
  background: green;
}
#target {
  left: 200px;
}
#hidden {
  background: red;
  view-transition-name: hidden;
}

html::view-transition-group(hidden) { animation-duration: 300s; }
html::view-transition-image-pair(hidden) { animation: unset; opacity: 0; }

/* The effect of the following should be position at the incoming element
   but contents of the new element.
*/
html::view-transition-group(shared) { animation-duration: 0s; }
html::view-transition-new(shared) { animation: unset; opacity: 1; }
html::view-transition-old(shared) { animation: unset; opacity: 1; }

html::view-transition-group(root) { animation: unset; opacity: 0; }
html::view-transition { background: lightpink; }

</style>

<div id=source></div>
<div id=target></div>
<div id=hidden></div>

<script>
failIfNot(document.startViewTransition, "Missing document.startViewTransition");

async function runTest() {
  source.style = "view-transition-name: shared";
  document.startViewTransition(() => {
    source.style = "";
    target.style = "view-transition-name: shared";

    requestAnimationFrame(() => requestAnimationFrame(takeScreenshot))
  });
}
onload = () => requestAnimationFrame(() => requestAnimationFrame(runTest));
</script>