Fatal error: Uncaught Error: Class "Psr\Log\AbstractLogger" not found in /var/www/user/valentin/home/projects/mpdf/vendor/psr/log/Psr/Log/NullLogger.php:13 Stack trace: #0 {main} thrown in /var/www/user/valentin/home/projects/mpdf/vendor/psr/log/Psr/Log/NullLogger.php on line 13