[lltx] microtype's \textls command broken in current TeX Live

[Reinhard Kotucha]

Dear Sirs,
the minimal example below doesn't work anymore.

---------------------------------------------------------------
\documentclass{article}
\usepackage{fontspec} \setmainfont{TeX Gyre Pagella}
\usepackage{microtype}
\usepackage{unicode-math} \setmathfont{texgyrepagella-math.otf}

\begin{document}
\textls[30]{$x$}
\end{document}
---------------------------------------------------------------

The problem occurs if the mandatory argument of \textls contains
stuff in math mode.  Any idea?  

Regards,
  Reinhard

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Reinhard Kotucha                            Phone: +49-511-3373112
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