<!doctype html>
<html>
  <head>
    <title>fractions linethickness</title>
    <meta charset="utf-8"/>
  </head>
  <body>

    <!-- This should draw fraction bars of increasing thickness -->
    <math mathsize="32px">
      <mfrac linethickness="thin"><mn>1</mn><mn>2</mn></mfrac>
      <mfrac linethickness="medium"><mn>1</mn><mn>2</mn></mfrac>
      <mfrac linethickness="thick"><mn>1</mn><mn>2</mn></mfrac>
      <mfrac linethickness="5"><mn>1</mn><mn>2</mn></mfrac>
    </math>

  </body>
</html>