protected function rescanDisplayOrder()
    {
        $displayOrder = 0;
        $btsID = $this->getBlockTypeSetID();
        $app = Application::getFacadeApplication();
        $db = $app->make(Connection::class);
        $rs = $db->executeQuery('select btID from BlockTypeSetBlockTypes where btsID = ? order by displayOrder asc', [$btsID]);
        while (($btID = $rs->fetchColumn()) !== false) {
            $db->update(
                'BlockTypeSetBlockTypes',
                [
                    'displayOrder' => $displayOrder,
                ],
                [
                    'btID' => $btID,
                    'btsID' => $btsID,
                ]
            );
            ++$displayOrder;
        }
    }