Hi,
I was migrating my app to v23 and I get a little outdated things on the docs and error message from getToken() modular function:

Due to a myself fault, my app didn't register the device to use Cloud messaging, so getToken() trew this error:

Error: [messaging/unregistered] You must be registered for remote messages before calling getToken, see messaging().registerDeviceForRemoteMessages().

This way of registering is outdated because registerDeviceForRemoteMessages() is a modular function too. And in the docs ( https://rnfirebase.io/messaging/usage#auto-registration-ios ) the way to register is outdated too in the same way, using deprecated namespace methods.

I solved my problem already, but I wanted to put my sand grain to support the project :)

Thanks and happy coding!