The new property nextDrawOnlyItems is an array that contains indexes for specific items to be written the next time the menu is drawn.  It can be used as a display optimization; for example, if the menu is redrawn in an input loop in the calling code and the selected item changed on the same 'page' on the menu, then the calling code can add the indexes of the 2 items to redraw the next the the menu is drawn so that the menu will only refresh those 2 items on the screen rather than the whole page of items.