if (this.props.handleCopy) {
            this.props.handleCopy({
              event: e,
              dataRenderer: dataRenderer,
              valueRenderer: valueRenderer,
              data: data,
              start: start,
              end: end,
              range: range,
            });                                 <== The return value is not being copied anywhere. 
          } else {
            var text = range(start.i, end.i)
              .map(function (i) {
                return range(start.j, end.j)
                  .map(function (j) {
                    var cell = data[i][j];
                    var value = dataRenderer ? dataRenderer(cell, i, j) : null;
                    if (
                      value === '' ||
                      value === null ||
                      typeof value === 'undefined'
                    ) {
                      return valueRenderer(cell, i, j);
                    }
                    return value;
                  })
                  .join('\t');
              })
              .join('\n');
            if (window.clipboardData && window.clipboardData.setData) {
              window.clipboardData.setData('Text', text);
            } else {
              e.clipboardData.setData('text/plain', text);
            }
          }