protected function _getActionGroups()
    {
        $action = $this->_action();
        $groups = $action->getConfig('scaffold.action_groups') ?: [];

        $groupedActions = [];
        foreach ($groups as $group) {
            $groupedActions[] = array_keys(Hash::normalize($group));
        }

        // add "primary" actions (primary should rendered as separate buttons)
        $groupedActions = (new Collection($groupedActions))->unfold()->toList();
        $groups['primary'] = array_diff(array_keys($this->_getAllowedActions()), $groupedActions);

        return $groups;
    }