public static function getExtConfPremium()
    {
        $keSearchPremiumIsLoaded = ExtensionManagementUtility::isLoaded('ke_search_premium');
        if ($keSearchPremiumIsLoaded) {
            $extConfPremium = GeneralUtility::makeInstance(ExtensionConfiguration::class)
                ->get('ke_search_premium');
            if (!$extConfPremium['prePostTagChar']) {
                $extConfPremium['prePostTagChar'] = '_';
            }
        } else {
            $extConfPremium = array();
        }

        // override extConfPremium with TS Setup
        if (is_array($GLOBALS['TSFE']->tmpl->setup['ke_search_premium.']['extconf.']['override.'])
            && count($GLOBALS['TSFE']->tmpl->setup['ke_search_premium.']['extconf.']['override.'])) {
            foreach ($GLOBALS['TSFE']->tmpl->setup['ke_search_premium.']['extconf.']['override.'] as $key => $value) {
                $extConfPremium[$key] = $value;
            }
        }

        return $extConfPremium;
    }