chromium/third_party/blink/web_tests/external/wpt/mathml/crashtests/mozilla/412237-1.xml

<html xmlns="http://www.w3.org/1999/xhtml">
<head>
</head>
<body>

<math xmlns="http://www.w3.org/1998/Math/MathML">
  <ms fontsize="-2%"><mfrac><mi>x</mi><mi>y</mi></mfrac></ms>
</math>

</body>
</html>