Device registration + push notifications vs. signal (?)

Fortsetzung der Diskussion von Molly-UP in Kuketz Blog:

Trying to find the hole in signal that drains the battery I got inspired by the above remark by @AnotherElk the other day.
I found that my device was never registered in microG and I wondered if that might help for timely reception of notifications and vs. battery drain…(battery drains less when energy consumption is restricted for background activities - but that makes notifications come in only when I open signal…)
So I registered my phone (auto: native) and allowed for push notifications but restricted permission for apps to ask first.
Nothing changes for signal (“normal” install from aurora store).
A few apps ask for permission (denied) but the one app that does not ask for permission is signal.
What´s the trick?

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