Undefined control sequence when using algorithm environment with dgruyter.sty

Question

I need to write a document using the dgruyter template. When I include an algorithm environment I get the following error.

Undefined control sequence.

<write> ...\protect \numberline {\plist@algorithm 
                                                  1}{\ignorespaces Alg\relax... l.32 \end{document}
                    The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g.,
`\hobx'), type `I' and the correct spelling (e.g., `I\hbox').
Otherwise just continue, and I'll forget about whatever was undefined.

MWE:

\documentclass[USenglish]{article}  

\usepackage[big,online]{dgruyter}

\usepackage{algorithm,algpseudocode}

\begin{document}
    
\begin{algorithm}[t]
\caption{Alg}
\begin{algorithmic}[1]
    \State Test
\end{algorithmic}
\end{algorithm}

\end{document}

An overleaf project with the files can be found here: https://www.overleaf.com/read/gnrtmsvxbsgt

Answer 1

Sigh, you should moan to the publishers, they should fix this

https://cs.uwaterloo.ca/twiki/view/CrySP/LaTeXSnippets

discusses several errors in this file including this one.

This works

\documentclass[USenglish]{article}  

\usepackage[big,online]{dgruyter}

\usepackage{algorithm,algpseudocode}
\makeatletter
\def\plist@algorithm{Alg.\space}
\makeatother
\begin{document}
    
\begin{algorithm}[t]
\caption{Alg}
\begin{algorithmic}[1]
    \State Test
\end{algorithmic}
\end{algorithm}

\end{document}