Hi Nasser,
> ====================================
> (/usr/local/texlive/2019/texmf-dist/tex/generic/tex4ht/html5.4ht)) (./foo.aux)
> ! Undefined control sequence.
> \\ ->\let \reserved@e
> \relax \let \reserved@f \relax \@ifstar {\let
> \reserv...
>
> l.101 \EndPreamble
> =======================
I don't get any error when I compile your mwe, it just doesn't work.
It works when I use the URL you pass in `\Configure{@HEAD}` to
\Configure{MathjaxSource}:
\Configure{MathjaxSource}{https://cdn.jsdelivr.net/npm/mathjax@3/es5/tex-mml-chtml.js}
I am bit surprised that I don't need to use \detokenize around TeX
macros in Mathjax configuration. I used some of your declared macros
and they seem to work.
Best regards,
Michal
