Questions about Proton Mail notifications and workarounds

zweig

I had a couple of questions regarding Proton Mail notifications workarounds on Graphene OS. I did my digging around forums and subreddits, but still don't understand a few things.

For Proton Mail notifications to work, I've seen that Google Play Services needs to be installed. I have them installed from day 1 of my GrapheneOS setup (without logging in to Google Play Store), and I still don't receive the notifications from ProtonMail (ProtonMail is installed through Obtainium/GitHub, and I also tried this before with the installation from Aurora Store). Why is that the case? Is full logging into the Google Play Store required for them to work? Please explain to me like I'm 5, because I have spent hours reading up on this, and I've only found information that Proton Mail uses Firebase Cloud Messaging (FCM), thus requiring Google Play Services, but not delving into the details and the experience that I have.
How safe is the ProtonMail + You Have Mail combo from a privacy standpoint, since I saw that You Have Mail requires a complete ProtonMail login info? I've tested this combo, and it works fine for now, but I was wondering if it's safe for future use.

23Sha-ger

zweig How safe is the ProtonMail + You Have Mail combo

You will have a mini-email client that will be constantly running in the background and pinging the server to
ask for new mails. While this might work, there is no way it can be even nearly efficient as FCM/UnifiedPush.

Most email clients (K9, FairEmail) can be configured to check for mails every X amount of time. That approach
is more efficient because at least it's an email client and not just an app distributing notifications.

zweig

23Sha-ger

I understand. I'm not worried too much about the efficiency (it's okay if notifications are late from time to time, as long as they are there). However, do you think that our privacy is compromised by using You Have Mail? And if yes, how much?

I'm currently using FairEmail for my other emails that I plan on abandoning and using ProtonMail only. However, I liked Proton's whole experience and was hoping to stay with their original app if possible.

taxonomy

This solution worked for me. It's all on device and not too difficult to set up.

Speeduser7533

I switched to Tuta for all of my important emails so those notifications don't get routed through google.

23Sha-ger

zweig
This is a helper app that is used as a distributor. Nothing directly related to privacy, however it's worth mentioning
that you have another app to include/exclude from a VPN, in case you use it in the same profile.
Proton clearly doesn't care about the whole situation so I would not be surprised if things will break when using 3d
party apps with future updates. Seems like a bigger overcomplex setup than just using a throw-away Google
account with sandboxed play services and efficient FCM. Or using their standalone APK which should fallback to
Websockets, the way Signal does. When you download it from Aurora, you download exact same copy as the one
from Play. So you arent fooling the app, rather than yourself. The app thinks you have play installed, but you don't.