texmath-0.6.7: tests/writers/munderover-04.tex
\underset{\phantom{\mathrm{fail}}}{\overset{\mathrm{top}}{\mathrm{-\ middle\ -}}}=\overset{\mathrm{top}}{\mathrm{-\ middle\ -}}\underset{\phantom{\mathrm{fail}}}{\overset{\mathrm{top}}{\mathrm{-\ middle\ -}}}=\overset{\mathrm{top}}{\mathrm{-\ middle\ -}}