android - Firestore what happens when an offline device goes online?

Question

I'm looking at firestore but the doc is very light on persistent data on android. My question is about the actions that will take place when the device comes back online.

Let's imagine that I have this low of data online:

MyCollection
| ----------------------- MyDocument (empty)

If I have two devices that synchronize with this model but are offline, both write in MyDocument, that device A created the field id with value A and that my device B also creates a fieldid with value B.

Devices A returns first online and then synchronizes with Firestore then device B returns online, problem the field id already exists with another value.

How will Firestore handle this knowing that it's done in the background automatically? Does it have a chance to catch redundancies to fix itself the problem?

Answer 1

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