% \subsubsection{XKCD}
% \DescribeMacro{\xkcd}{Reference an XKCD cartoon.}
%    \begin{macrocode}
%<*classXimera>
\newcommand{\xkcd}[1]{#1}
%</classXimera>
%    \end{macrocode}
% On the web, this should be an image linked to the actual XKCD website.
%    \begin{macrocode}
%<*htXimera>
\renewcommand{\xkcd}[1]{\ifvmode \IgnorePar\fi \EndP\HCode{<img src="https://imgs.xkcd.com/comics/#1.png">}}
%</htXimera>
%    \end{macrocode}