texmath-0.8: tests/writers/mfracZcomp-20.tex
\text{Inline\ double\ down\ arrows,\ display\ style,\ thick\ line~}\left. \Downarrow\frac{\sin\theta}{M}\Downarrow \right.\text{~the\ end.}
\text{Inline\ double\ down\ arrows,\ display\ style,\ thick\ line~}\left. \Downarrow\frac{\sin\theta}{M}\Downarrow \right.\text{~the\ end.}