PHP:
Fatal error: Uncaught Error: Class "Psr\Log\AbstractLogger" not found in /www/habi.gna.ch/doc/u/includes/vendor/psr/log/Psr/Log/Test/TestLogger.php:57 Stack trace: #0 {main} thrown in /www/habi.gna.ch/doc/u/includes/vendor/psr/log/Psr/Log/Test/TestLogger.php on line 57