5.12.0 windows/Windows 10 (10.0), DPR=2, windowsvista ()
v_ScreenNumber= 0 v_ScreenOffset= QPoint(0,0) QSize(1920, 1080) wid 0x10010 GetDesktopWindow= 0x10010
v_FullWindowWrong= QPixmap(QSize(3840, 2160),depth=32,devicePixelRatio=2,cacheKey=0x300000871)
v_FullWindowOk= QPixmap(QSize(3840, 2160),depth=32,devicePixelRatio=2,cacheKey=0x600000871)

C:\dev\projects\qtbug70933_512>debug\qtbug70933.exe
5.12.0 windows/Windows 10 (10.0), DPR=2, windowsvista ()
v_ScreenNumber= 1 v_ScreenOffset= QPoint(3840,0) QSize(1920, 1200) wid 0x10010 GetDesktopWindow= 0x10010
v_FullWindowWrong= QPixmap(QSize(1, 1),depth=32,devicePixelRatio=1,cacheKey=0x300000001)
v_FullWindowOk= QPixmap(QSize(1920, 1200),depth=32,devicePixelRatio=1,cacheKey=0x5000004b0)

C:\dev\projects\qtbug70933_512>debug\qtbug70933.exe
5.12.0 windows/Windows 10 (10.0), DPR=2, windowsvista ()
v_ScreenNumber= 1 v_ScreenOffset= QPoint(3840,0) QSize(1920, 1200) wid 0x10010 GetDesktopWindow= 0x10010
v_FullWindowWrong= QPixmap(QSize(1, 1),depth=32,devicePixelRatio=1,cacheKey=0x300000001)
v_FullWindowOk= QPixmap(QSize(1920, 1200),depth=32,devicePixelRatio=1,cacheKey=0x5000004b0)