If the Show link on any non-current revision of an item's History view is clicked, then that revision is displayed with the normal set of Item Views. There is no indication that the item displayed is not the current revision.
If the revision displayed is a deleted revision, then clicking the Delete button (and perhaps other buttons as well) results in a traceback.
If the modify button is clicked, the current version is edited. If the last item revision is a deleted revision, then any newly saved revision is also marked deleted (trash=True in meta data).
A possible resolution is to restrict the entries within Item Views whenever a non-current revision is displayed to:
- Download (if the revision being downloaded is the one shown)
- Meta (if the meta shown matches the revision)