src/Doc/Demo_FoilTeX/document/root.tex

treat map_filter similar to list_all, list_ex, list_ex1

\documentclass[a4paper,landscape]{foils}
\usepackage[utf8]{inputenc}
\usepackage{amssymb}
\usepackage[svgnames]{xcolor}
\usepackage{graphicx}
\usepackage{isabelle,isabellesym}
\usepackage{isabellefoils}
\usepackage{pdfsetup}

\parindent 0pt\parskip 0.5ex

\urlstyle{sf}
\isabellestyle{it}
\MyLogo{}

\isadroptag{theory}
\isafoldtag{proof}


\begin{document}

\title{\titlestyle Simple slides with FoilTeX}
\author{Makarius Wenzel, Augsburg \\ \url{https://sketis.net}}
\date{}
\maketitle

\vfill

\begin{center}
  \includegraphics[width=0.15\textwidth]{isabelle_logo}
\end{center}

\vfill

\input{session}

\end{document}