I've found the following Github repository with the typscripts definitions:
https://github.com/r3n4ud/roboto-context
When I use this type-imp-roboto.mkiv file fonts are used and embedded
when using Roboto in thes \setupbodyfont[].
When I use ebgaramond as the body font but use:
\switchtobodyfont[roboto,20pt] in the \setuphead[] call the font is not
embedded and seems to be not used.
I am more optimistic but still confused what can be wrong.
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