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Files inside a Composition or a Folder will not be displayed inside the link manager.
Illustrator
Insert asset
In version 5.7 and later, if a user tries to insert a non-document asset into PSD/AI when there is no active document present, a new empty document will be added before the asset is inserted.
Link Manager
Local assets cannot be <Linked file> or <Image> since it will breaks the link manager.
Photoshop
Insert asset
In version 5.7 and later, if a user tries to insert a non-document asset into PSD/AI when there is no active document present, a new empty document will be added before the asset is inserted.
Link Manager
The files within the link manager are smart objects and cannot be modified if they need to be visible in the link manager. However, assets within the active document can be manually converted into smart objects in order to be displayed in the link manager.
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