Sort / order by supplier on order detail page

[lucifer_1]

Recently we finally moved to Prestashop 1.7 from 1.6.

In 1.6 we did some finetuning, as we have thousands of products, and on order contains often more then 100 products. That is why we changed the sort of the products on the order detail page by supplier id.

I have search for hours for an solution and found only one, but it isn't working.

This is the class/order/orderdetail.php

    public static function getList($id_order)
    {
        return Db::getInstance()->executeS('SELECT * FROM `' . _DB_PREFIX_ . 'order_detail` WHERE `id_order` = ' . (int) $id_order.' ORDER BY supplier_id ASC');
    }