"Cloning: allow linked cloning" ?
How it works?
In Vmware 7.x it allows to create differencing image of VM-B based on differencing image VM-A. (so I can create new linked VM B, based on a snapshot of VM A)
But AFAIK, VBox disallows to create differencing image from previous differencing image. (except for one VM, branched snapshots)
If we allow linked cloning from GUI, then multi-attach images may become extinct species.