Per-device presence. (SYN-217)

[matrixbot]

In order to intelligently push the right devices, we need to track how idle given devices are. This means at letting the local HS track per-device presence, and being able to relay it per-device to interested application services.

(Imported from https://matrix.org/jira/browse/SYN-217)

(Reported by @ara4n)

[matrixbot]

Jira watchers: @ara4n

[DMRobertson]

It's not clear what this is asking for. What is the use case? Why do application services care?

[DMRobertson]

This has sat silent for 8 years. I suggest we give @ara4n a week to explain what this means, or otherwise close it.

[anoadragon453]

Synapse could withhold push notifications from certain devices today based on presence data, though it's not currently defined here which presence states should prevent a push notification from coming through. Perhaps "busy" (MSC3026)?