k rel=help href="https://drafts.csswg.org/css-display-3/#internal-ruby-element">

<style>
div {
  overflow: hidden;
  position: absolute;
}
rtc {
  contain: size;
  display: ruby-text-container;
  font-size: 1rem;
}
</style>

<p>This test passes if you can see the word PASS below.
<div><ruby><rtc>PASS</rtc></ruby></div>
