chromium/third_party/blink/web_tests/printing/fixedpos-in-fixedpos.html

<!DOCTYPE html>
<script>
  if (window.testRunner)
    testRunner.setPrinting();
</script>
<style>
  body {
    margin: 0;
  }
</style>
<div style="position:fixed; top:100px; left:100px;">
  On every page<br>
  <div style="position:fixed; top:150px; left:100px;">
    Also on every page
  </div>
</div>
<div style="height:300vh;"></div>