I need to send targeted messages to users, but when I look at the fcm_tokens subcollection, there are a lot of documents. For example, here are the tokens for one user
I want to be able to send the notification to multiple devices if the user has multiple devices, but I think this collection includes old tokens that are no longer valid for the same device.
Does this collection ever get cleaned up?
What's the best way to choose the correct token(s) to send a message right now?