[Wish] Request access to shares - Sign-up as guests

[gymnae]

It would be great if instead of a push, there could also be a pull mechanic for guests.
The idea:
When someone without a user or guest account attempts to access a share, they are greeted with the ability to either login, or request a guest account. A request requires choosing a username and setting email and password.

The request is then received and reviewed by the user creating the share, or the admin, granting access. The following logic is is that of a normal guest account, with only initial access to the share behind the initial link.

If an existing guest user tries to follow a link to another share, the person sharing that folder receives a request for review. Thus, a guest user could access different shares.