Ability to Obsolete Folders & Notify Owner
Add an option under the folder settings ([?] button), under Sharing, add an item for Obsolete Folder which upon selecting would go to a simple page stating that clicking Ok will notify the Folder Owner(s) that you believe this folder is obsolete and should be deleted.
Additionally, when selecting Remove, to Remove as Collaborator, that page can also have an option to notify the Owner(s) that the folder looks to be obsolete and is suggested to be deleted.
1
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This addresses a narrow use case without adding value to a significant amount of our users.
There is also a current way to achieve this by emailing the owner to ask them to delete the folder.