[NTG-context] Problem with \dfrac{}{} with lmtx updated

Hi, I just updated lmtx and I don't understand the error that occurs with the \dfrac{}{}. Thank you. Fabrice ##################### \starttext \m{f(x)=\dfrac{a + b\ln(x)}{x}} \stoptext ##################### tex error > tex error on line 2 in file ./hans_21.tex: Math error: parameter 'fractionnumup' in style 2 is not set <macro> \math_m_nop #1->\relax \ifmmode #1\else \normalstartimath #1\normalstopimath \fi \m{f(x)=\dfrac{a + b\ln(x)}{x}} 1 \starttext 2 >> \m{f(x)=\dfrac{a + b\ln(x)}{x}} 3 \stoptext Sorry, but I can't typeset math unless various parameters have been set. This is normally done by loading special math fonts into the math family slots. Your font set is lacking at least the parameter mentioned earlier. mtx-context | fatal error: return code: 256 TeX Output exited abnormally with code 1 at Thu Dec 24 16:30:13