# [dev-context] small bug with the 'frac' font feature and linux libertine

Hans Hagen j.hagen at xs4all.nl
Fri Jan 18 14:26:13 CET 2019

```On 1/18/2019 1:31 PM, Taco Hoekwater wrote:
> Hi,
>
> One of Hans van der Meer’s notes has this definition:
>
>    \definefontfeature[fraction][frac=yes]
>    \definehighlight[textfraction][style={\feature[+][fraction]}]
>
> but 'frac' sadly does not quite work correct with Linux Libertine.
>
> It looks like somehow the substitution context is off when
> the command is used immediately after a digit? I am not sure how
> to debug this properly, nor how to fix it even if I could find
> root cause of the problem, so I am posting here in the hope
> someone knows how to fix it.

i never rely on frac (often implemented incomplete in fonts)

Hans

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