Fatal error: Uncaught Error: Interface "Laravel\SerializableClosure\Contracts\Signer" not found in /home/bimmertest/BookStack/vendor/laravel/serializable-closure/src/Signers/Hmac.php:7 Stack trace: #0 {main} thrown in /home/bimmertest/BookStack/vendor/laravel/serializable-closure/src/Signers/Hmac.php on line 7