content-visibility-auto-resize.html

<!DOCTYPE html>
<title>Layout Instability: resizing content-visibility:auto content</title>
<link rel="help" href="https://wicg.github.io/layout-instability/" />
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="resources/util.js"></script>
<script>
// These scripts need to be before the contents because we need to ensure no
// layout shifts during page load.
promise_test(async () => {
  const watcher = new ScoreWatcher;

  // Wait for the initial render to complete.
  await waitForAnimationFrames(2);

  assert_equals(watcher.score, 0);
}, 'off-screen content-visibility:auto');
</script>
<style>
  .auto {
    content-visibility: auto;
    contain-intrinsic-size: 10px 3000px;
    width: 100px;
  }
  .contained {
    height: 100px;
    background: blue;
  }
</style>
<div class=auto><div class=contained></div></div>
<div class=auto><div class=contained></div></div>

chromium/third_party/blink/web_tests/external/wpt/layout-instability/content-visibility-auto-resize.html