The active area of the rightmost inventory sort button "O" extends right about three button widths outside the button itself. It also overextends a bit downwards (like all the other sort buttons). This does not cause problems as there is no other active element under the invisible button area. It does prevent using that particular location for dragging the screen, which is a very minor issue. The bug is not a problem in practice, it's just a bit funny seeing the mouse pointer change and the button tooltip appear when the mouse is well to the right of the sort buttons. The bug shows up in all screens using an item inventory area.
