The native react-markdown code renderer should be used for syntax highlighting customization.

[shammamah-zz]

I think the existing implementation does not take full advantage of the react-markdown ability to get its renderer overriden -- similarly to https://github.com/plotly/dash-core-components/pull/711/files#diff-5b56ed82805404e28302aef5147d04a2R129 it should be possible to hook up the highlight directly onto the code renderer and simplify this component / usage.

Originally posted by @Marc-Andre-Rivet in #720