I can see my icons on the desktop with Firefox settings on Max. I have tried power down Firefox, shutdown the computer and stop Speed Dial. When I turn off my Speed Dial on Firefox the problem goes away. Since I have several pages of Speed Dial and I know the locations of popular dials, I miss the dials. So I live with the problem. If I do fresh start on Firefox after boot up the problem is gone for awhile but as the day hours increases so does the gap. The problem is with second screen in background updating the dials and working screen will not slide past the second screen.
Customer support service by UserEcho