TL;DR

I'm listening to Firestore changes using a snapshot. Snapshots documents are from cache. How can I indicate whether a DocumentSnapshot has delivered or not? Is there any flag which can indicate it?

More info

I'm developing a chat application, and I want to implement a "message not delivered" icon next to the message, same as WhatsApp does (on no network connection).

I'm using Firestore to collect my messages, and I'm listening to updates using a snapshot. Since I'm using Firestore snapshot, I'm getting my messages from the cache, while the cache itself updates on every change (which is pretty cool).

My issue is that I cannot indicate whether each message was delivered successfully or not.

A good use case is a user, with no network connection, that is sending a message, then closes the app, and re-opens it (without any network, cached only). I need to indicate to them that the last message has still not been delivered.