\let\mypdfximage\pdfximage\def\pdfximage{\immediate\mypdfximage}\documentclass[twoside]{book}

%% moved from doxygen.sty due to workaround for LaTex 2019 version and unmaintained tabu package
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\else
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%%
% Packages required by doxygen
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\usepackage{doxygen}
\usepackage{graphicx}
\usepackage[utf8]{inputenc}
\usepackage{makeidx}
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% Arguments of doxygenemoji:
% 1) ':<text>:' form of the emoji, already "LaTeX"-escaped
% 2) file with the name of the emoji without the .png extension
% in case image exist use this otherwise use the ':<text>:' form
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% Page & text layout
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\makeatletter
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% Headers & footers
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%
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%
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\renewcommand{\sectionmark}[1]{%
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% Indices & bibliography
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\usepackage[titles]{tocloft}
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\makeindex

\usepackage{newunicodechar}
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\usepackage{caption}
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\usepackage{etoc}
\etocsettocstyle{\doxytocparskip}{\doxynormalparskip}
\renewcommand{\numberline}[1]{#1~}
%===== C O N T E N T S =====

\begin{document}
\raggedbottom

% Titlepage & ToC
\hypersetup{pageanchor=false,
             bookmarksnumbered=true,
             pdfencoding=unicode
            }
\pagenumbering{alph}
\begin{titlepage}
\vspace*{7cm}
\begin{center}%
{\Large BJ-\/\+Keyer \\[1ex]\large 1.\+03 }\\
\vspace*{1cm}
{\large Erzeugt von Doxygen 1.9.1}\\
\end{center}
\end{titlepage}
\clearemptydoublepage
\pagenumbering{roman}
\tableofcontents
\clearemptydoublepage
\pagenumbering{arabic}
\hypersetup{pageanchor=true}

%--- Begin generated contents ---
\chapter{Ausstehende Aufgaben}
\label{todo}
\Hypertarget{todo}
\input{todo}
\chapter{Datenstruktur-\/\+Verzeichnis}
\input{annotated}
\chapter{Datei-\/\+Verzeichnis}
\input{files}
\chapter{Datenstruktur-\/\+Dokumentation}
\input{structConfig}
\input{structMenuCtrl}
\input{structMessage}
\input{structSerialState}
\input{structState}
\chapter{Datei-\/\+Dokumentation}
\input{controls_8c}
\input{controls_8h}
\input{encoder_8c}
\input{encoder_8h}
\input{functions_8c}
\input{functions_8h}
\input{globals_8h}
\input{main_8c}
\input{main_8h}
\input{vt100_8c}
\input{vt100_8h}
%--- End generated contents ---

% Index
\backmatter
\newpage
\phantomsection
\clearemptydoublepage
\addcontentsline{toc}{chapter}{\indexname}
\printindex

\end{document}