I found how to open the dev menu

How do you open the dev menu? If you are not doing revealed map, does it render enemy's units/structures that you can't see/haven't seen?

What do you mean? Implemented but not shown? I can't see it anywhere in the web page. Is it also a team Glicko-2 version? Edit: Ah! Found it at the player site, when you click on a player

What you mention is called culling, you can see what's being culled through the dev menu, by locking the camera frustrum. The problem is that at low angles, it's almost impossible to cull stuff, because you see an infinite distance forward. Other than that it's already implemented.

Glicko2 is already implemented in Replay Pallas.