src/Debug/Utf8.php
public static function addSpecial($special)
    {
        $special = (array) $special;
        foreach ($special as $char) {
            self::$special[] = $char;
        }
    }
public static function addSpecial($special)
    {
        $special = (array) $special;
        foreach ($special as $char) {
            self::$special[] = $char;
        }
    }
Add additional characters to be treated as special chars

@param array|string $special character or array of characters ore regular-expressions

@return void