public function activatePlugin($pluginSlug)
    {
        $plugins = (array)$pluginSlug;
        foreach ($plugins as $plugin) {
            $option = '//*[@data-slug="' . $plugin . '"]/th/input';
            $this->scrollTo($option, 0, -40);
            $this->checkOption($option);
        }
        $this->scrollTo('select[name="action"]', 0, -40);
        $this->selectOption('action', 'activate-selected');
        $this->click("#doaction");
    }