The path to the default keyboard layouts does not exist on NixOS and possibly other systems. However, registering and unregistering the default keyboard layouts is not needed as the registered modified layouts resource is accessed with higher priority than the original layouts resource until it is unregistered.
Additionally, the resources were not being unregistered since a reference to the original Gio.Resource object is needed to unregister it. Creating a new resource by loading it from the same path does not create the same resource reference. The unregistering appeared to work because new resources were continuously registered above the old ones.
The path to the default keyboard layouts does not exist on NixOS and possibly other systems. However, registering and unregistering the default keyboard layouts is not needed as the registered modified layouts resource is accessed with higher priority than the original layouts resource until it is unregistered.
Additionally, the resources were not being unregistered since a reference to the original Gio.Resource object is needed to unregister it. Creating a new resource by loading it from the same path does not create the same resource reference. The unregistering appeared to work because new resources were continuously registered above the old ones.