There is a folder whose collaboration is allowed for only internal ( At folder settings, Restrict collaboratio within our company is checked )
One unmanaged user who uses company email domain but is associated with free box account is invited the folder, he/she is successfully invited. But auto expirtation for external collaborators ( which is set on enterprise settings) is also adopted to the user. This seems unnatrual and it is not reasonable.

This is said by design, but could you consider improvng either 1 or 2 ?
1. if a folder is only allowed to collaborate internal, please restrict unmanaged users have been invited it.

1. If an unmanaed user is able to be invited in a folder only for internals, please handle the unamnaged user as same as managed users. don't treat like external users.

1 is best for us, for some particular reasons we can not use auto-rollin feature, and some part of users who use happened to make free box accounts by themseves.