ErrorBag is always empty in Laravel 5.2

I was creating a new Laravel project and when debugging the errors of a form request, I noticed that my ErrorBag was always empty. Even when in the controller $validator->fails() returned true. I tried every solution I found on the internet but nothing worked.

Even when creating a fresh project with composer (as described here) my out of the box auth system has an empty error bag when leaving all the field empty.

And yes, all the routes are using the middleware group web.

Any ideas what is causing this problem? (Session::put() and Session::get() are working)

via Chebli Mohamed