protected function getCustomizedRuleKeysToExclude(array $customRules)
    {
        $keys = [];

        foreach ($customRules as $key => $ruleParts) {

            // If the set value for this key is false/null, the rule must be ignored entirely.
            // This will disable enrichment using form field rules.
            if (false === $ruleParts || empty($ruleParts)) {
                $keys[] = $key;
            }
        }

        return $keys;
    }