# Error: adding includegraphics in argument of section or subsection with tableofcontents

I'm using the following code but when I want to add \includegraphics{example-image-duck} to argument of section or subsection I got error in this case @Skillmon suggest to add \protect which gives \section{\protect\includegraphics{example-image-duck}} but even though I got error besides I get another error from that code as soon as I use \tableofcontents.

\documentclass{report}
\usepackage[utf8]{inputenc}
\usepackage{xcolor}
\usepackage[Lenny]{fncychap}
\usepackage{graphics}
\usepackage{graphicx}
\usepackage{float}
\usepackage[explicit]{titlesec}
\usepackage{soul}

\definecolor{titleblue}{HTML}{4a7aa4}

\title{Sections and Chapters}
\author{Educ}
\date{\today}

\newbox\TitleUnderlineTestBox
\newcommand*\TitleUnderline[1]
{%
\bgroup
\setbox\TitleUnderlineTestBox\hbox{\colorbox{titleblue}\strut}%
\setul{\dimexpr\dp\TitleUnderlineTestBox-.3ex\relax}{.3ex}%
\ul{#1}%
\egroup
}
\newcommand*\SectionNumberBox[1]
{%
\colorbox{titleblue}
{%
\makebox[2.5em][c]
{%
\color{white}%
\strut
\csname the#1\endcsname
}%
}%
\TitleUnderline{\ \ \ }%
}
\titleformat{\section}
{\Large\bfseries\sffamily\color{titleblue}}
{\SectionNumberBox{section}}
{0pt}
{\TitleUnderline{#1}}
\titleformat{\subsection}
{\large\bfseries\sffamily\color{titleblue}}
{\SectionNumberBox{subsection}}
{0pt}
{\TitleUnderline{#1}}

\begin{document}

\maketitle
\tableofcontents
\chapter{Lenny}
\chapter{Lenny}
\section{Use this Tools \includegraphics[width=1cm]{example-image-duck} to obtain random points in Geogebra}
\section{Plya's Problem-Solving Cycle}
\subsection{Understand the problem}
\subsection{Devise a Plan}
\subsection{Carry Out the Plan}
\subsection{Look Back}
\section{Second Section}

\section
{Really long section name that is really long, so long it takes two rows}

\end{document}

• No need to load graphics if you then load graphicx. – Skillmon May 1 '18 at 11:37
• \protect\includegraphics works fine for me. But you should delete the old toc. – Ulrike Fischer May 1 '18 at 11:39
• works fine with \protect\includegraphics[width=1cm]{example-image-duck} – user36296 May 1 '18 at 11:40
• @UlrikeFischer funny. I used article in my tests (because the first question was using article), and there I get the error ! Argument of \@mkboth has an extra }.. As soon as I use report everything works fine. – Skillmon May 1 '18 at 11:43
• @Skillmon you could get the correct line by adding a \mbox around the graphics (to hide it from soul). But with article it will fail for the \section inside \tableofcontents. I would never use soul here -- much too fragile. – Ulrike Fischer May 1 '18 at 11:54