code: function (td) {
        var coords = self.view.getCellCoords(td);
        var corners = grid.getCornerCoords([priv.selStart, priv.selEnd]);
        if (priv.settings.fillHandle !== 'horizontal' && (corners.BR.row < coords.row || corners.TL.row > coords.row)) {
          coords = {row: coords.row, col: corners.BR.col};
        }
        else if (priv.settings.fillHandle !== 'vertical') {
          coords = {row: corners.BR.row, col: coords.col};
        }
        else {
          return; //wrong direction
        }
        autofill.fillBorder.appear([priv.selStart, priv.selEnd, coords]);
      }
docs: Show fill border