This feature Setting Item Level Restriction is introduced in LUNA v7.4.3 and this feature is located in the LUNA Library. It allows for restricting media items or media items & records in a collection and then granting access to those restricted items to a smaller set of users. Restrictions are applied to items both in the Viewer and the Library (not one or the other). Super Admins and the owner of a collection have full access to all items, regardless of the restriction. A collection owner can also pass collection ownership to another user and in doing so the previous collection owner will no longer have the collection owner status.
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