docs: protected void moveSelectionUp() {
  		final IStructuredSelection selection = this.list.getStructuredSelection();
  		final int index = this.conversions.indexOf(selection.getFirstElement());
  		if (index > 0) {
  			final ConversionMapping previous = this.conversions.remove(index - 1);
  			this.conversions.add(index + selection.size() - 1, previous);
  			refreshListUI();
  			this.list.refresh(true);
  			enableButtons();
  			preferenceValueChanged();
  		}
  	}