Cannot do a full clone of a snapshot if a parent snapshot is using an unavailable cd/dvd media

[ctrl]

I have this (maybe messed up) situation:

+Snapshot 1 using a dvd iso I don't have anymore on disk
++Snapshot 2 using the same iso
+++Snapshot 3 *not* using the iso
++++Current state

I want to full clone snapshot 3 to a new vm and get rid of this vm, because I cannot remove the dvd iso from the snapshot 1&2: if I revert to snapshot 1 and unlink the iso, when I step forward to snapshot 2 I still have snapshot 1 (unchanged, obviously) using it, so I cannot remove that iso from the media manager. Also, I cannot delete snapshot 2 and then 1 (which I both don't need), because I'm getting an error like "more than one child hdd image", which is not true btw.

So.. I try to clone snapshot 3 to a new vm and when it's almost finished it complains it cannot link iso_from_first_snapshot.iso to the image because it's already present in the media manager. And it's true that it's there... because I cannot delete it.

I can post logs and error messages if needed, but it takes a bit to clone it again...

[aeichner]

Please reopen if still relevant with a recent VirtualBox release.