docs: protected void moveSelectionBottom() {
  		final IStructuredSelection selection = this.list.getStructuredSelection();
  		final int index = this.conversions.indexOf(selection.getFirstElement());
  		if (index >= 0 && (index + selection.size()) < this.conversions.size()) {
  			for (int i = 0; i < selection.size(); ++i) {
  				final ConversionMapping previous = this.conversions.remove(index);
  				this.conversions.addLast(previous);
  			}
  			refreshListUI();
  			this.list.refresh(true);
  			enableButtons();
  			preferenceValueChanged();
  		}
  	}