Syntax highlighting not applied to PascalCase-named files

Question

I was renaming files from a DSA class when I realized that files named in PascalCase lacked the syntax highlighting present in files named in lowercase.

Here is a PascalCase filename:

Here is a lowercase filename:

I tried some alternatives, and it looks like the highlighting changes if there's at least one uppercase character in the filename. I poked around the settings but found nothing. Anyone experience this before?