Discovered something very odd while setting colors

I do not know where else to put this, but I discovered this very odd behavior while setting up experimenting with theme and preferences.

As you may know, operator highlighting does not work, but it appears the editor.operator.style can still be used to add more keywords. In this case I made my preprocessor directives purple.

In keywords.txt I added:

#include KEYWORD4
#define KEYWORD4
#undef KEYWORD4
#if KEYWORD4
#ifdef KEYWORD4
#ifndef KEYWORD4
#endif KEYWORD4
#error KEYWORD4

And in themes.txt this sets the color of KEYWORD4:

editor.operator.style = #FF00FF,bold