%%
%% The LaTeX Companion, 3ed
%%
%% Example A-4-5 on page II-680 in "Hooks provided for \protect \nxLcs  {shipout} operations".
%%
%% 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{106.20108pt}


  %--------------------------------------
  % For the book example we have to do some special paper dimensions here.

  \setlength\textheight{106pt}


  \usepackage[%
    textheight=\textheight,
    paperheight=\dimexpr\textheight+4pt,
    textwidth=\textwidth,
    paperwidth=\dimexpr\textwidth+2pt,
    ]
    {geometry}


  % So the above should not be copied into your own document preamble.
  %--------------------------------------

  \usepackage{microtype} % improve justification in small columns

%StartShownPreambleCommands
\usepackage{kantlipsum,graphicx,color}
\AddToHook{shipout/background}
  {\put(.5\paperwidth,-.5\paperheight)
    {\makebox(0,0){\includegraphics
             [scale=.7]{latex-logo}}}}
%StopShownPreambleCommands

\begin{document}
\kant[1][1-2] % text by the author ...
 \AddToHookNext{shipout/foreground}
   {\put(0,-\paperheight)
      {\colorbox{red}{Censor this!}}}
\kant[1][3]   % ... more text ...
\end{document}