Re: [NTG-context] underbraces get progressively more misaligned (w/ minimal example)

Wolfgang Schuster writes:

math-stc.mkvi:

% - \ifx\currentmathtext\empty + \ifx\m_math_stackers_text_middle\empty \setbox\scratchboxthree\emptyhbox

Is this change still also needed (in addition to the luatex fix)? -Sanjoy