mubeamer is not compatible with ignorenonframetext

The mubeamer package is not compatible with the ignorenonframetext option of beamer. The following example cannot be compiled by pdflatex with MU theme:

\documentclass[ignorenonframetext]{beamer}
\usetheme[workplace=mu]{MU}
\begin{document}
\begin{frame}{Test Slide}
  Test
\end{frame}
\end{document}

It works fine without \usetheme{MU}.

The ignorenonframetext option is generated by pandoc in default settings.

The problem could be solved by adding \beamer@ignorenonframefalse to beamerthemeMU.sty, more details could be found at stackexchange.