Verbatim environment

Use the verbatim environment with small text (\small\begin{verbatim}) causes error in
the mdframe environment. To solve this, use the fancyvrb package with

\begin{Verbatim}[fontsize=\small]
\end{Verbatim}

Verbatim environment and mdframe package

When using an mdframed package to create a box around the verbatim environment,

\surroundwithmdframed[style=bluebox]{Verbatim}

the text following the environment becomes white. To fix this, use the fancyvrb package
and set the box to the Verbatim environment instead:

\usepackage{fancyvrb}
\surroundwithmdframed[style=bluebox]{Verbatim}