%%
%% The LaTeX Companion, 3ed
%%
%% Example 4-2-43 on page I-322 in "Extension to inline verbatim by fvextra".
%%
%% Copyright (C) 2022 Frank Mittelbach
%%
%% It may be distributed and/or modified under the conditions
%% of the LaTeX Project Public License, either version 1.3c
%% of this license or (at your option) any later version.
%%
%% See https://www.latex-project.org/lppl.txt for details.
%%

\documentclass{tlc3exa}
\pagestyle{empty}
\setcounter{page}{6}
\setlength\textwidth{207.0pt}

  \setlength\parindent{0pt}

  \setlength\marginparwidth{28pt}
  \addtolength\textwidth{-\marginparwidth} % make room on the page
  \addtolength\textwidth{-\marginparsep}   % in the book example

  % small headings for the example
  \makeatletter
  \renewcommand\section{\@startsection{section}{1}{\z@}%
    {-1.25ex \@plus-1ex \@minus-.2ex}%
    {.5ex}%
    {\normalfont\large\bfseries}}
  \renewcommand\subsection{\@startsection {subsection}{2}{\z@}%
    {-1.ex \@plus -.5ex \@minus -.2ex}%
    {.3ex}%
    {\normalfont\bfseries}}
  \makeatother

  \usepackage{microtype} % to improve h&j in example

%StartShownPreambleCommands
\usepackage{fvextra}
%StopShownPreambleCommands

\begin{document}
\tableofcontents \medskip
\section{\EscVerb*{Space  \\danger \ \{\%}}
\EscVerb{\\EscVerb*{...}} is not dangerous
and can\marginpar{\EscVerb[fontsize=\tiny]
                          {No \\danger \#}}
be used anywhere.
\subsection{\Verb*{Space   \danger  {}}}
And this works with limitations in
\textsf{fvextra}.
\end{document}