Hi warjort thanks. My usecase is for a Map key that provides easy access to the key (ResourceLocation) & registered object (Item/Block/EntityType..).
Prior to 1.19 I used forge's `IRegistryDelegate` as keys in a long living Maps, as they stored a reference to the actual object as well as the resource location of that object in the registry. Using the delegate as a key was better as the equality of two registry items could be compared through the delegates using equals and you wouldn't need to store underlying object which could change and causing memory leaks. I'm not up to speed but perhaps this isn't want I need anymore. Using the resource location as a key and doing a look up in the relevant registry may be the way forward..