mozilla-release/testing/web-platform/tests/mathml/presentation-markup/radicals/radical-rendering-from-in-flow-ref.html

<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8"/>
    <title>radicals rendering from in-flow children</title>
  </head>
  <body>
    <math>
      <msqrt>
        <mspace width="64px" height="8px" style="background: lightblue"></mspace>
      </msqrt>
      <mroot>
        <mspace width="64px" height="12px" style="background: lightblue"></mspace>
        <mspace width="128px" height="24px" style="background: lightgreen"></mspace>
      </mroot>
    </math>
  </body>
</html>