I would like to vertically aling an equation number for the following MWE:
\documentclass{scrartcl} \usepackage{amsmath} \usepackage{mathtools} \begin{document} \begin{align} \begin{aligned} a &= b \\ &= \underbrace{d+e}_{\substack{\text{Long}\\\text{text}}} \end{aligned} \end{align} \begin{equation} \begin{multlined} a+b+c+d+e+f+{}\\ g+h+i+\underbrace{i+j}_{\substack{\text{Long}\\\text{text}}} \end{multlined} \end{equation} \end{document} In both cases underbrace increases the size of the second line and thus, the equation number is not exactly between the two lines. How do I fix this?
This question can be understood as a follow up question of A vertically centered equation number on a multline environment.

