private function _do_never_allowed_afterwards(string $str): string
    {
        if (\stripos($str, 'on') !== false) {
            foreach (self::$_never_allowed_on_events_afterwards as $event) {
                if (\stripos($str, $event) !== false) {
                    $regex = '(?<before>[^\p{L}]|^)(?:' . $event . ')(?<after>\s|[^\p{L}]|$)';

                    do {
                        $count = $temp_count = 0;

                        $str = (string) \preg_replace(
                            '#' . $regex . '#ius',
                            '$1' . $this->_replacement . '$2',
                            $str,
                            -1,
                            $temp_count
                        );
                        $count += $temp_count;
                    } while ($count);
                }
            }
        }

        return (string) \str_ireplace(
            self::$_never_allowed_str_afterwards,
            $this->_replacement,
            $str
        );
    }
private function _do_never_allowed_afterwards(string $str): string
    {
        if (\stripos($str, 'on') !== false) {
            foreach (self::$_never_allowed_on_events_afterwards as $event) {
                if (\stripos($str, $event) !== false) {
                    $regex = '(?<before>[^\p{L}]|^)(?:' . $event . ')(?<after>\s|[^\p{L}]|$)';

                    do {
                        $count = $temp_count = 0;

                        $str = (string) \preg_replace(
                            '#' . $regex . '#ius',
                            '$1' . $this->_replacement . '$2',
                            $str,
                            -1,
                            $temp_count
                        );
                        $count += $temp_count;
                    } while ($count);
                }
            }
        }

        return (string) \str_ireplace(
            self::$_never_allowed_str_afterwards,
            $this->_replacement,
            $str
        );
    }
private function _do_never_allowed_afterwards ( string $ str ) : string { if ( \ stripos ( $ str , 'on' ) !== false ) { foreach ( self :: $ _never_allowed_on_events_afterwards as $ event ) { if ( \ stripos ( $ str , $ event ) !== false ) { $ regex = '(?<before>[^\p{L}]|^)(?:' . $ event . ')(?<after>\s|[^\p{L}]|$)' ; do { $ count = $ temp_count = 0 ; $ str = ( string ) \ preg_replace ( '#' . $ regex . '#ius' , '$1' . $ this -> _replacement . '$2' , $ str , - 1 , $ temp_count ) ; $ count += $ temp_count ; } while ( $ count ) ; } } } return ( string ) \ str_ireplace ( self :: $ _never_allowed_str_afterwards , $ this -> _replacement , $ str ) ; }
Remove never allowed string, afterwards.

<p>
<br />
INFO: clean-up also some string, if there is no html-tag
</p>

@param string $str

@return  string
Remove never allowed string afterwards .