I noticed that safeURL don't work for topics in Polish language, for example:

Zażółć gęślą jaźń

So in /sys/CODOF/Filter.php I changed line:

$str = mb_convert_encoding((string) $str, 'UTF-8', mb_list_encodings());

to this:

$str = iconv("UTF-8", "UTF-8//IGNORE", $str);
$str = iconv("UTF-8", "ASCII//TRANSLIT", $str);

I always use it in my projects and it works well.
http://sandbox.onlinephpfunctions.com/code/110e68c61166d8e57cba4254dec55e72fcbc3061

But... When I created for test new topic: "Zażółć gęślą jaźń" my safeURL is:

zaz-oacute-l-c-ge-sla-ja-z-n

instead of:

zazolc-gesla-jazn

Why i have a lot of additional "-" ?
Do you know how to fix this bug?

This depends of PHP version: http://stackoverflow.com/a/38709208

Titles in Polish are broken in database:

ó is replaced by &oacute ;

Which version of codoforum are you using ?

We will test those characters.

Which version of codoforum are you using ?

We will test those characters.

Codoforum v3.6

Here is a working demo: http://sandbox.onlinephpfunctions.com/code/3ca9951ddfe725703235f0472a754b9fe4a9d7fd

$str = 'Zażółć gęślą jaźń';
    $a = array('/ą/', '/ż/', '/ź/', '/ę/', '/ć/', '/ń/', '/ó/', '/ł/', '/ś/', '/Ą/', '/Ż/', '/Ź/', '/Ę/', '/Ć/', '/Ń/', '/Ó/', '/Ł/', '/Ś/');
    $b = array('a', 'z', 'z', 'e', 'c', 'n', 'o', 'l', 's', 'A', 'Z', 'Z', 'E', 'C', 'N', 'O', 'L', 'S');
    $str = preg_replace( $a, $b, $str );
    echo $str;

Is there any htmlentities in topic title when saving title to the database?
I'm trying to find where is function, which changes my title before it is saved to database.

ok, so I have solution:

in sys/CODOF/Format.php I commented out line 135 and set htmlspecialchars:

// $mesg = htmlentities($mesg, ENT_NOQUOTES, "UTF-8");

 
 
 
This is ok for me:

    public static function title($mesg) {

        //$mesg = str_replace("<", "<", $mesg);
        //$mesg = str_replace(">", ">", $mesg);
        $mesg = htmlspecialchars($mesg);
        // $mesg = htmlentities($mesg, ENT_NOQUOTES, "UTF-8");
        return $mesg;
    }

 
 
In next step I need to set 'transliterate' to true.

 
In sys/CODOF/Filter.php line 36:

'transliterate' => true,

In the end I changed line:

    $str = mb_convert_encoding((string) $str, 'UTF-8', mb_list_encodings());

to:

  //$str = mb_convert_encoding((string) $str, 'UTF-8', mb_list_encodings());
    $str = mb_convert_encoding((string) html_entity_decode($str), 'UTF-8', mb_list_encodings());

Result:

Regards!

I don't know why this problem is repeating again because we had already fixed accented characters.

Thankyou for sharing the solution.