public function addCustomButton($iconName, array $params = [], $hashTarget = '')
    {
        $customButtons = is_array($this->getOption('customButtons')) ? $this->getOption('customButtons') : [];
        $customButtons[] = ['iconName' => $iconName, 'params' => $params, 'hashTarget' => $hashTarget];
        return $this->setOption('customButtons', $customButtons);
    }