Thanks. That works.

After I add that option into the pygments drop-down choice, will it automatically switch to that syntax highlight?

Will it use the same syntax highlight though out Differential, Audit and Diffusion?

will it automatically switch to that syntax highlight?

I don't think so; It tries to use the file name by default (You can teach it to map a file name to a language with syntax.filemap).

Will it use the same syntax highlight though out Differential, Audit and Diffusion?

Yes (Technically, the screen you're seeing it on is Audit, and Diffusion doesn't have the Highlight As option yet).
Any place that allows you to select highlighting uses the same list of options.

wow, thank you so much for the detailed answer. So much appreciated.