docs: private final void _tryUnlink() {
          if (0 >= _cursorCount && _state == LOGICALLY_UNLINKED) {
              _previousLink._nextLink = _nextLink;
              _nextLink._previousLink = _previousLink;
              _previousLink = null;
              _nextLink = null;
              // Defect 240039
              //_parent = null;
              _state = PHYSICALLY_UNLINKED;
          }
      }