I'd like to understand how much of a privacy risk it is to get notifications from my apps via FCM (thus with the sandboxed google services installed in my main profile with network permissions).
I understand that ProtonMail, for instance, encrypts the notifications as well so Google cannot see them. Is that standard practice? Does Signal, for instance, do the same? For apps that aren't focused on privacy, should I expect that they do not implement any kind of encryption for notifications and that therefore Google can see them?
Thanks a lot in advance. I'm not on GrapheneOS yet and I'm trying to best understand how I could set it up for my personal case before I buy a Pixel.