Our monitoring system shows this error logs sporadically on any kind of requests. We cannot reproduce it locally and we have a Prod Environment with 25 FPM instances and it happens to occur on different instances. We work with symfony and a lot of different composer packages of course.
This is the exact Error message (anonymized)
Cannot declare class ComposerAutoloaderInit{placeholder for an ID}, because the name is already in use in /home/vcap/app/vendor/composer/autoload_real.php on line 5