Does the notification tell you about the collapse_key restriction message?

Question

According to the Firebase notification documentation :

Notification messages are always discarded.

I tried to find out if they have a built-in collapse_key . And if so, is it calculated to the limit of collapse_key 4 per device?

Answer 1

You're right. All notifications sent from the web console are collapsible.

That means they have an implicit collapse_key

If your device has pending messages from the web console,
this implicit collapse_key counts to a limit of 4 per device.