I have never seen anything like this. I was trying to follow a tutorial on how to use the new 2.8 interface, but when I switch into edit mode, it looks nothing like the 2.7x mode. My screen has what looks like vertices projected from the object and stretched. Keep in mind, all I'm trying to do is extrude a cube's face. I have had some very limited success by messing with the overlays tab at the top right of the screen.