public function getFlashKeys(): array
	{
		if (! isset($_SESSION['__ci_vars']))
		{
			return [];
		}

		$keys = [];
		foreach (array_keys($_SESSION['__ci_vars']) as $key)
		{
			is_int($_SESSION['__ci_vars'][$key]) || $keys[] = $key;
		}

		return $keys;
	}