bug#68992: 13.3.0; not displaying \newcommand defintions

[Sabarish V M]

Hi,

The preview latex package does not render the "\newcommand" macros
properly.

Example,

\documentclass{template}
\title{Some title}
\author{XXX}
\begin{document}
\maketitle

\include{symbols} % The file contains all the macros defined
% It contains,
% \newcommand{\kb}{k_{\mathrm{B}}}
% \renewcommand{\d}{\mathrm{d}}

From classical Boltzmann statistics we know that the probability for finding any
particle in a given state $i$ is,
\[ \frac{N_i}{N} = \frac{\exp \left( - E_i / \kb T \right)}{Z\kb \d } \]
\include{chapters/01.introduction}
\include{chapters/appendix}

\end{document}

The symbol \kb and \d are not rendered at all. Sometimes they are
rendered and other times it throws an error saying "undefined symbols”.

Best,
Sabarish.