\setupbodyfont[xits,10pt]

\starttext

\setupmathematics[default=normal]

\startformula
    \startalign
        I &= ∫_S d(x)\, dx \NR
        I &= ∫_S 𝑑(x)\, dx \NR
        I &= ∫_S d(x)\, \mathupright{d} x \NR
        I &= ∫_S 𝑑(x)\, \mathupright{d} x \NR
    \stopalign
\stopformula

\stoptext
