The issue for Proton Mail inclusion is here: https://gitlab.com/fdroid/rfp/-/issues/1323
TL;DR: It uses proprietary components (Google Mobile Services and Google Firebase).
So it still works on my degoogled phone. I assume that means the google components are integrated?
They are but they wonโt have the desired functionality. You wonโt get push notifications for instance.
I think, what @muntedcrocodile@lemm.ee means with โintegratedโ, is that theyโre wholly part of the app and donโt depend on Googley software being installed into the OS. And to my knowledge, that is not the case.
So, thereโs a client library which you include into your app code. That talks with the Google Play Services on your phone. And that then talks with some Google server.
I assume, that client library itself is already proprietary and thatโs why the F-Droid team strictly needs to have it removed. Ideally, it would be replaced by an open-source alternative, but the code could also be modified to not include this library and youโd โonlyโ lose e.g. push notifications. Depending on how the app is implemented, you might not get notifications at all then, though.
But they donโt go lightly about modifying the code of an app. If the developer doesnโt want this, they can pull all kinds of shenanigans to make this more difficult or impossible for the F-Droid teamโฆ
