page_with_positioned_nested_frames.html

<!DOCTYPE html>
<style>
iframe {
  position:absolute;
  top: 50px;
  left: 50px;
  width: 200px;
  height: 200px;
}
</style>
<html>
<body>
<iframe src="/cross-site/a.com/frame_tree/page_with_positioned_frame.html"></iframe>
This page contains a nested and positioned cross-origin frames.
</body>
</html>

chromium/content/test/data/frame_tree/page_with_positioned_nested_frames.html