When in windowed mode the plugins available screen size is correct, i.e. you can ctrl hash and move any plugin toolbar anywhere on the screen.
When in full screen mode the dragable window size is reduced to about one quarter of the screen (top left region). So when plugins load on startup, they are positioned in the top left quarter of the screen and cannot be repositioned outside of this quarter using ctrl hash unless you switch to windowed mode.
I guess this is same for other users?