This issue is fixed, indeed.

About \columncolor which would take precedence over \rowcolor, that's not what I notice with the MCE of this issue.

Hi,

tex4ht is aware of \columncolor and rowcolor colortbl's commands but, surprisingly enough, (silently) it ignores \cellcolor:

\documentclass{article}
\usepackage{colortbl}
\usepackage{array}
%
\newcolumntype{A}{>{\columncolor{green}}l}
%
\begin{document}
\begin{tabular}{lA}
\cellcolor{red} foo & bar \\
\rowcolor{blue} bar & foo
\end{tabular}
\end{document}