View and Remove Orphan Stashes
Oprhan Stashes are stashes, that are no longer referenced by any scene objects.
The View Oprhans tool is essentially the same as the ViewStashes tool, except it accessed orphan stashes, instead of object stashes.
The Remove Orphans tool is used to permantly remove orphan stashes from the blend file.
Once this is done, the stash object is lost, and can't be retrieved anymore.
The tools do not require any selection, only the presence of orphan stashes in the blend file.