Unified Push Notifications

[ereio]

Add ability to choose between background sync thread or a unified push instance.

https://unifiedpush.org/developers/flutter

[genofire]

The Application-Server, like the Matrix-Instance, send a Push Message to an Push Gateway (e.g. FCM, UnifiedPush).
The Distributer Application, like Gotify or GoogleServices, has a Persistent Connection to the Push Gateway and recieve the Push Massage . So the Application, like Syphon, could be wake up by Distributer Application and tell it, that the Matrix-Instance has new messages.

For more details read the Website of https://unifiedpush.org/
A good starting point: https://unifiedpush.org/spec/definitions/

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The Benefits of it is to safe battery, that Android just keep one connection to Push Gateway and not every Application holds one Connection. The Applications could also stopped and recieve new state out of the Internet.

It depends on the Application, but the information of the new state, could also received earlier. Like an the application pulls every x minutes.

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By the way, for browser with "closed" Website exists also an PushAPI: https://developer.mozilla.org/en-US/docs/Web/API/Push_API

It could ("just") popup Notifications, if you allow it in your browser.

[genofire]

The Matrix Client Fluffychat support already UnifiedPush and Elements has his second PR for it: element-hq/element-android#3448