protected function checkAttributeFilters(array $attributes)
	{
		foreach ($attributes as $attrConfig)
		{
			if (empty($attrConfig['filterChain']))
			{
				continue;
			}
			foreach ($attrConfig['filterChain'] as $filter)
			{
				if (substr($filter, 0, 1) !== '#' && !in_array($filter, $this->allowedFilters, true))
				{
					throw new RuntimeException("Filter '$filter' is not allowed in media sites");
				}
			}
		}
	}