With MAGNOLIA-3285, we fixed the virtual uri registration so that a mis-configured node would still be wrongly transformed into a Map, by catching ClassCastException while iterating through mappings. Such mis-configured nodes should simply not be added to the list of mappings. This would allow using generics, too (if we used generics without fixing this first, we'd get ClassCastException when attempting to add mis-configured mappings to the info.magnolia.cms.beans.config.VirtualURIManager#cachedURImapping list)