code: def auto_scroll(self, thumbkey):
          
          if not self.gui_up:
              return
          # force scroll to bottom of thumbs, if checkbox is set
          scrollp = self.w.auto_scroll.get_state()
          if not scrollp:
              return
  
          bnch = self.thumb_dict[thumbkey]
  
          # override X parameter because we only want to scroll vertically
          pan_x, pan_y = self.c_view.get_pan()
          self.c_view.panset_xy(pan_x, bnch.image.y)
docs: Scroll the window to the thumb.