% Created 2022-10-12 Wed 04:43
% Intended LaTeX compiler: lualatex
\documentclass[11pt]{article}
\usepackage{fontspec}
\usepackage{graphicx}
\usepackage{longtable}
\usepackage{wrapfig}
\usepackage{rotating}
\usepackage[normalem]{ulem}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage{capt-of}
\usepackage{hyperref}
\author{Gerard Vermeulen}
\date{\today}
\title{Table fails LuaLaTeX compilation}
\hypersetup{
  pdfauthor={Gerard Vermeulen},
  pdftitle={Table fails LuaLaTeX compilation},
  pdfkeywords={},
  pdfsubject={},
  pdfcreator={Emacs 28.2 (Org mode 9.6-pre)},
  pdflang={English},
  citecolor=blue,
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  linkcolor=blue,
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}
\usepackage{biblatex}
\addbibresource{~/VCS/research/refs.bib}
\begin{document}

Macro \colorbox{red}{\texttt{works outside table}} but fails inside tables where
\texttt{\textbackslash{}\textbackslash{}} matters. The \LaTeX{} export fails to compile because of \texttt{\textbackslash{}\textbackslash{}\textbackslash{}relax}
instead of \texttt{\textbackslash{}\textbackslash{}}:

\begin{center}
\begin{tabular}{l}
\hline
\colorbox{red}{\texttt{bug}}\\\relax
\colorbox{red}{\texttt{bug}}\\\relax
\hline
\end{tabular}
\end{center}
\end{document}