I have reported this a few month ago but since it has not been fixed, I thought that it may have been forgotten. Try running xelatex on this minimal example:
\documentclass{article} \usepackage{fontspec} \defaultfontfeatures{Numbers=OldStyle,Mapping=tex-text} \setmainfont{Junicode} \begin{document} \(\mathbf{0123xyzjh}\) \end{document} log complains that: Unknown feature `' in font `JunicodeRegular'. Unknown feature `' in font `JunicodeRegular'. This is not a problem but when preview package is used: \documentclass{article} \usepackage[xetex,tightpage,active,textmath]{preview} \usepackage{fontspec} \defaultfontfeatures{Numbers=OldStyle,Mapping=tex-text} \setmainfont{Junicode} \begin{document} \(\mathbf{0123xyzjh}\) \end{document} Then you get error: ! Package xkeyval Error: no key specified for value `'. See the xkeyval package documentation for explanation. Type H <return> for immediate help. ... l.5 \setmainfont{Junicode} ?
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