code: def get_scrollbar_position_height(self):
          
          vsb = self.editor.verticalScrollBar()
          style = vsb.style()
          opt = QStyleOptionSlider()
          vsb.initStyleOption(opt)
  
          # Get the area in which the slider handle may move.
          groove_rect = style.subControlRect(
                  QStyle.CC_ScrollBar, opt, QStyle.SC_ScrollBarGroove, self)
  
          return float(groove_rect.height())
docs: Return the pixel span height of the scrollbar area in which
          the slider handle may move