In this example there is no kerning and no ligatures in the math: \starttext WAiff $\mfunction{WAiff}$ \stoptext This is a different behaviour than with legacy math fonts. A question about this has been asked some month ago on tex.sx (http://tex.stackexchange.com/questions/252493/ligatures-are-not-used-in-open...). The problem (or feature) exist also with xetex. With luatex one can avoid to loose the kerning by loading as math roman font a font in mode base (http://tex.stackexchange.com/questions/277362/lualatex-no-kerning-within-ope..., I have no idea how to do this in context). Is this a luatex/xetex bug? Or a feature? How could one enable kerning and/or ligatures without going back to base mode? -- Ulrike Fischer http://www.troubleshooting-tex.de/