unicode-math override's fontspec's \setmathsf & co

[wspr]

Here's the problem:

\documentclass{article}
\usepackage{fontspec}
\setmathsf{texgyrecursor-regular.otf}
\usepackage{unicode-math}
\begin{document}
$\mathsf{X}=X$
\end{document}

Also see #404.