!!DON'T USE FULLSCREEN!! Instead zoom in on the player page. Using full screen in 150% zoom fixes the issue.
Warning for bratty snobs: Slightly less high FPS (20 fps) on fullscreen. This actually varies from 10 to 350 fps. I don't know why. Planned: building price shows only when you mouseover that building. This was not originally intended, but my text drawing system means I can only draw about 14 numbers to the screen before Scratch runs out of clones.