I cloned my notebook display to TV set through HDMI but when I run an arena on full screen the display size gets the same on both displays and it's too big. The TV set is 32'' but it can't fit the full size of the broadcasting and you need to scroll in order to see the rest parts of the picture. When you scroll, the mouse cursor goes beyond the picture frame and the frame stands in the middle of the screen. May be I explained it too complicated but this is it.
Anyone who can give me an advice how to overwhelm this issue will be blessed till the end of days