Text Formatting ⇒ (soul or soulutf8) + microtype = ☇

[user49915]

Continuing https://github.com/latex3/babel/issues/ ... -598474037 and https://github.com/latex3/babel/issues/ ... -598530361 here (as the issue is unrelated to babel), consider feeding
\documentclass{article}
\usepackage{microtype}
\usepackage{soul}

% this is the default for textsterling and it works
\DeclareTextCommandDefault{\textsterling}{\UseTextSymbol{TS1}{\textsterling}}
\DeclareTextSymbol\textsterling{TS1}{163}

% this one fails also fails if I point to OT1
% the moment microtype is added

\DeclareTextCommandDefault{\textsterling}{\UseTextSymbol{T1}{\textsterling}}
\DeclareTextSymbol\textsterling{T1}{191}

\begin{document}
\pounds

\hl{a b \pounds{} c}
\end{document}
to pdflatex. The error message you get is "! Package soul Error: Reconstruction failed."