Mathieu, I lied to you. After I changed the "index" to my own title, I started getting
[phpBB Debug] PHP Notice: in file /includes/functions.php on line 3391: Cannot modify header information - headers already sent by (output started at /language/en/common.php:1)
[phpBB Debug] PHP Notice: in file /includes/functions.php on line 3393: Cannot modify header information - headers already sent by (output started at /language/en/common.php:1)
[phpBB Debug] PHP Notice: in file /includes/functions.php on line 3394: Cannot modify header information - headers already sent by (output started at /language/en/common.php:1)
[phpBB Debug] PHP Notice: in file /includes/functions.php on line 3395: Cannot modify header information - headers already sent by (output started at /language/en/common.php:1)
I tried to remove lines 3391,3393,3394,3395 from functions.php, but it caused more trouble lol
Do you know the magic spell for this problem too?
