Fatal error: Uncaught TypeError: mysqli_query(): Argument #1 ($mysql) must be of type mysqli, null given in /home/httpd/vhosts/o-i-s.ch/httpdocs/classes/DB_class.php:38
Stack trace:
#0 /home/httpd/vhosts/o-i-s.ch/httpdocs/classes/DB_class.php(38): mysqli_query(NULL, 'SELECT `id_cont...')
#1 /home/httpd/vhosts/o-i-s.ch/httpdocs/classes/content_Generator_class.php(28): DB->query('SELECT `id_cont...')
#2 /home/httpd/vhosts/o-i-s.ch/httpdocs/index.php(7): ContentGenerator->GetContent('index.php')
#3 {main}
  thrown in /home/httpd/vhosts/o-i-s.ch/httpdocs/classes/DB_class.php on line 38