This is something I ran into while working on a fix for the `TestBed` module teardown behavior for #18831. In the `RouterInitializer.appInitializer` we have a callback to the `LOCATION_INITIALIZED` which has to do some DI lookups. The problem is that if the module is destroyed before the location promise resolves, the `Injector.get` calls will fail. This is unlikely to happen in a real app, but it'll show up in unit tests once the test module teardown behavior is fixed.
PR Close#42560