After I upgraded PHP version of my website to 7.3, the website does not work properly. It shows only blank pages. After my investigation, I found that the problem is in this line:
ini_set('session.save_handler', 'user');
As I see in php.ini, the default value is "files". I try to change the value to files, but it's the same. Until PHP 7.1, everything works fine, but on PHP 7.2 and PHP 7.3, I have this problem. I really can't understand why this function not working. It doesn't return any error, just a blank page with code 200 (not 500 as server error).
How do I solve this problem?
PHP >7.2 dropped ini_set('session.save_hanlder','user').
Use the session_set_save_handler(); instead (https://www.php.net/manual/en/function.session-set-save-handler.php).
You can find the announcement in the changelog here https://www.php.net/ChangeLog-7.php#7.2.0 look under the "Session" section.
It references a bug https://bugs.php.net/bug.php?id=73100.