If you think it is a system problem and not a context one, then:

fc-cache -fv

-m

On February 20, 2017 8:24:07 AM PST, Nicola <nvitacolonna@gmail.com> wrote:
>Hello everyone,
>I am re-typesetting a mkiv document that uses system fonts for text and
>math (through \definefontfamily). Suddenly, it renders Latin Roman for
>the text. May it be a cache corruption problem? I recall that there's
>a command to clear the font cache, but I cannot remember which.
>
>
>Nicola
>
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