Description
Proxy generator is creating __sleep method with uninitialized typed properties which is a critical bug since PHP 7.4.2 (https://bugs.php.net/bug.php?id=79002) ending in message:
Typed property Proxies_CG_\App\Entity\EntityName::$ must not be accessed before initialization (in __sleep)
I've already reported it (not knowing the source of error hence the wrong repo) in doctrine/orm#8030 but it looks like it's stuck there forgotten.