`unscoped` often has an effect broader than intended. For instance:
```
user.dossiers.unscoped.destroy_all
```
will not destroy all the user's dossier, including the hidden ones,
but **all the dossiers of all users**.
Instead, narrower unscoping should be used:
```
user.dossiers.unscope(where: :hidden).destroy_all
```
(Or even better, use the new `Dossier.with_hidden` scope).
