public function manyManyExtraFieldsForComponent($class, $component)
    {
        // Get directly declared many_many_extraFields
        $extraFields = Config::inst()->get($class, 'many_many_extraFields');
        if (isset($extraFields[$component])) {
            return $extraFields[$component];
        }

        // If not belongs_many_many then there are no components
        while ($class && ($class !== DataObject::class)) {
            $belongsManyMany = Config::inst()->get($class, 'belongs_many_many', Config::UNINHERITED);
            if (isset($belongsManyMany[$component])) {
                // Reverse relationship and find extrafields from child class
                $belongs = $this->parseBelongsManyManyComponent(
                    $class,
                    $component,
                    $belongsManyMany[$component]
                );
                return $this->manyManyExtraFieldsForComponent($belongs['childClass'], $belongs['relationName']);
            }
            $class = get_parent_class($class);
        }
        return null;
    }