# "Unknown slot number of character" with microtype and siunitx

This MWE produces the following warnings:

\documentclass{article}
\usepackage{microtype}
\usepackage[detect-all]{siunitx}
\begin{document}
\num{1e-3}
\end{document}


I receive 5 warnings similar to this one (if I change the order of the two packages, the number of warnings increases to 34):

Package microtype Warning: Unknown slot number of character
(microtype)                \textminus '
(microtype)                in font encoding TS1' in protrusion list
(microtype)                textcomp'.


I suspect these have been introduced by recent update of something (probably not microtype nor siunitx themselves). Can I get rid of these warnings without silencing them?

\documentclass{article}
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