I had that as well. You need to play in full-screen mode, but make sure to click the blue full-screen icon!
did not work for me :( i tried the windows version too and am still having the issue. maybe its a monitor resolution thing? i assumed it was somehow intentional til i saw the screenshots
Weird, I checked in both 1080 and a 1440 monitors, and it works fine if I click the blue icon...