Fatal error: During inheritance of IteratorAggregate: Uncaught ArgumentCountError: Too few arguments to function default_error_handler(), 4 passed in /var/www/web25939799/html/schwarmlernen/lib/navigationlib.php on line 893 and exactly 5 expected in /var/www/web25939799/html/schwarmlernen/lib/setuplib.php:421 Stack trace: #0 /var/www/web25939799/html/schwarmlernen/lib/navigationlib.php(893): default_error_handler(8192, 'Return type of ...', '/var/www/web259...', 1138) #1 /var/www/web25939799/html/schwarmlernen/lib/setup.php(599): require_once('/var/www/web259...') #2 /var/www/web25939799/html/schwarmlernen/config.php(27): require_once('/var/www/web259...') #3 /var/www/web25939799/html/schwarmlernen/index.php(30): require_once('/var/www/web259...') #4 {main} in /var/www/web25939799/html/schwarmlernen/lib/navigationlib.php on line 893