texmath-0.7: tests/writers/mfenced-08.tex
\left| \begin{array}{l}
U \\
V \\
\end{array} \right| = \left\| \begin{array}{l}
U \\
V \\
\end{array} \right\|
\left| \begin{array}{l}
U \\
V \\
\end{array} \right| = \left\| \begin{array}{l}
U \\
V \\
\end{array} \right\|