Switch between in-window control and full screen in Remote Desktop
You can control a computer either through the control window or using the entire administrator computer screen. The “Fit screen to full display” button toggles between these two modes.
In in-window mode, you can switch between fitting the client screen in the window or showing it actual size, possibly scrolling around the window to see the entire client screen. In full-screen mode, the client computer screen is scaled up to completely fill the administrator screen. In addition to the client screen, there are a number of Remote Desktop controls still visible overlaying the client screen.