\documentclass{beamer}
\usepackage{soul,color}
\begin{document}
\begin{frame}
\hl{Hello World}
\end{frame}
\end{document}
I process this with pdflatex and I do not see the expected highlight.
If I try to assign a color to overstrike same thing happens, as in
\setstcolor{red}
\st{Hello}
but \st{hello} by itself does overstrike hello in black when no color is set.
Why is that and what is a work-around? Many That I tried do not work with long text.
The Soul Package Documentation, footnote 5, says something about needing a Postscript driver.
I do not have a problem using soul package outside of beamer.

\ul{...}. Could you add a bit of explanation how? Thanks! – fuenfundachtzig Jul 09 '18 at 21:20\ul, you would of course need to add something like\makeatletter \let\UL\ul \renewcommand\ul{\let\set@color\beamerorig@set@color \let\reset@color\beamerorig@reset@color \UL} \makeatother(so just replace\hlby\uland\HLby\ULin the above code). – Jasper Habicht Nov 18 '22 at 21:05