chromium/third_party/blink/web_tests/external/wpt/html/semantics/popovers/popover-anchor-transition.tentative.tentative.html

<!DOCTYPE html>
<meta charset="utf-8">
<title>Tests transitioning display property of anchored popover</title>
<link rel="help" href="https://html.spec.whatwg.org/multipage/popover.html">
<link rel="help" href="https://github.com/whatwg/html/pull/9144">
<link rel="author" href="mailto:[email protected]">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>

<style>
body {
  margin: 0;
}

#target {
  inset: auto;
  transition: display 2s;
}
</style>

<div popover anchor id="target">
  Popover
</div>

<script>
test(() => {
  target.showPopover();
  const xBefore = target.offsetLeft;
  const yBefore = target.offsetTop;

  target.hidePopover();
  assert_equals(target.offsetLeft, xBefore, 'Should not shift in x axis');
  assert_equals(target.offsetTop, yBefore, 'Should not shift in y axis')
}, 'Transitioning display property of an anchored popover should not cause a position shift');
</script>