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  case CheckBox_StayOnTop.Checked of
    True:
      begin
        Application.MainForm.Borderstyle := bsNone;
        Application.MainForm.FormStyle := fsStayOnTop;
        Application.MainForm.WindowState :=  wsMaximized;
        SetWindowPos(Handle, HWND_TOPMOST, 0, 0, 0, 0, SWP_DRAWFRAME or SWP_NOMOVE or SWP_NOSIZE);
      end;
    False:
      begin
        Application.MainForm.Borderstyle := bsSizeable;
        Application.MainForm.FormStyle := fsNormal;
        Application.MainForm.WindowState :=  wsNormal;
        SetWindowPos(Handle, HWND_NOTOPMOST, 0, 0, 0, 0, SWP_DRAWFRAME or SWP_NOMOVE or SWP_NOSIZE);
      end;
  end;
  Application.Processmessages;