mathbackground-4-ref.xml
<!-- test mathbackground on a non-presentation element -->
<math xmlns="http://www.w3.org/1998/Math/MathML">
<semantics mathbackground="red">
<mtext>□■□■□■□</mtext>
</semantics>
</math>
<!-- test mathbackground on a non-presentation element -->
<math xmlns="http://www.w3.org/1998/Math/MathML">
<semantics mathbackground="red">
<mtext>□■□■□■□</mtext>
</semantics>
</math>