I've upgraded 2 laravel applications on 5.4 few months ago.
Those application were created on 5.1, and I've always follow the upgrade guide 1 month after any release publication.
Since 5.4, I often have this kind of error on POST request :
Illuminate\Contracts\Encryption\DecryptException·The payload is invalid app/Http/Middleware/CheckForMaintenanceMode.php:43App\Http\Middleware\CheckForMaintenanceMode::handle throw new HttpException(503); } return $next($request); //line 43 } }
I don't have it on webhook notifications, it's always made by user request (session modification, on entity modification, etc).