[HybridStatAnim8]

This is not an issue with GrapheneOS, this is an issue with your configuration, which is trivial to solve.

All of those apps support using google services FCM for push notification delivery. I dont think Telegram has a fallback, and Signal and Whatsapp have power-intensive fallbacks. You may also need to reinstall these apps for them to detect google services (apps generally dont check for google services more than once on initial launch).

[classified]

That's not how I understand the meaning of "trivial".

[lnfromx]

You just have to reinstall you apps using Google Play Store and install Google Play Services

[yolo1897]

No, whatsapp fallback to websockets is very power efficient unlike official signal app one, all you need is to set battery optimization to unrestricted for it.

[lnfromx]

I doubt that however an app solves this problem without FCM or Unified Push can be called power efficient.