[firebase_messaging] How to group notifications when App is in Background

[Nidal-Bakir]

While creating the Messaging App. If the User is not on the App and gets the message from the other device, the device receives notifications but gets different notifications for each message for the same user. There is no such option to group/combine notifications & cancel the old notifications with the new ones.
the #1736 and #1770 are closed without the right solution!! by reading the docs for collapsekey
the solution offered by @Salakar this comment is not applicable in this scenario.
what I need to achieve 👇️