What does Elo and Simplification mean under dev type?

We all know what non functional means, but how about Elo and Simplification?

Thanks!

Yup! So I’m still figuring this out myself a little bit. My best understanding right now is that:

Simplifications are changes that remove lines, refactor, or otherwise simplify the code base.

Elo means that the change was specifically made to increase the engine’s strength.