% Created 2017-03-12 Sun 14:09
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\author{Eric S Fraga}
\date{\today}
\title{}
\hypersetup{
 pdfauthor={Eric S Fraga},
 pdftitle={},
 pdfkeywords={},
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 pdfcreator={Emacs 26.0.50.1 (Org mode 9.0.4)}, 
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\begin{document}

\section{highlighting text}
\label{sec:org4ba738a}
This is \hl{some text} that should be highlighted.

\begin{mdframed}
Here are two paragraphs that should be highlighted.

This is the second of them.
\end{mdframed}

And we continue with normal text.
\end{document}