public function invalidateSourceCacheTag(Contao\DataContainer $dc, array $tags)
	{
		$commentModel = Contao\CommentsModel::findByPk($dc->id);

		if (null !== $commentModel)
		{
			$tags[] = sprintf('contao.comments.%s.%s', $commentModel->source, $commentModel->parent);
		}

		return $tags;
	}