texmath-0.7: tests/writers/msubsup-09.tex
M_{B_{4}^{3}}^{T_{2}^{1}} = M_{B_{\underset{\phantom{\text{0}}}{4}}^{3}}^{T_{2}^{\overset{\phantom{\text{0}}}{1}}}
M_{B_{4}^{3}}^{T_{2}^{1}} = M_{B_{\underset{\phantom{\text{0}}}{4}}^{3}}^{T_{2}^{\overset{\phantom{\text{0}}}{1}}}