Worst Bug: holding W (run) and pressing Return (to start a chat)

W+Return causes you to go from full screen to windowed mode. And if you hit return a couple times to try to get chat started you get put in a look of windowed mode (renders) then full screen (renders) then windowed mode (renders) then full screen (renders) then windowed mode (renders) then full screen (renders) then windowed mode (renders) then full screen (renders) then windowed mode (renders) then full screen (renders) then windowed mode (renders) then full screen (renders) then windowed mode (renders) then full screen (renders) then windowed mode (renders) then full screen (renders) then windowed mode (renders) then full screen (renders) then

I think you get the idea. Imagine having 3 minutes left to extract and your screen is resizing non-stop over and over for a solid 2 minutes. Horrible bug.