GrapheneOSGoogle and carriers deployed changes to RCS which have been breaking it for many users on the stock OS including with certain carriers and in whole countries. The changes appear to have specifically impacted GrapheneOS users too. It's not related to our September 8th update. We're working on it.
You can find many recent threads about people having issues with RCS in Google Messages while using a stock OS with Google Mobile Services. There are articles about how some carriers and countries no longer have it. It still works for most people but the changes definitely regressed compatibility.
GrapheneOS users were impacted by these recent changes much more than other users. We don't know why yet but we're working on determining that and restoring compatibility with Google Messages for people who use it. We'll try to get compatibility with the new way it functions implemented very soon.
Re4mstr@GrapheneOS are there any official 'minimal' way of getting rcs? I gave up on it a couple of months ago, cause no guides worked.
@Re4mstr Google Messages is the only available option and is being quite hostile to being used elsewhere without privileged integration into the OS. We're going to work on fixing it but we can't guarantee it will work long term. We need an open source RCS app and it's not really clear how open RCS is to having alternate implementations. It's hard to see that as simply being openly allowed when Google Messages is mainly failing due to privileged verification checks it wants to do.
Marlow@GrapheneOS Also to my understanding there is no reason for this from a security perspective. To me if things such as Signal, Matrix apps, Therma, and Session can work then there is no reason this couldn't and still be "secure".
I don't like the security of RCS but it's better then nothing to me and also just convenient because it's hard to get people to use alternatives.
@emberfox The reason for it would be that it could have interoperable end-to-end encryption with Google Messages. iOS hasn't added RCS end-to-end encryption yet but supposedly will in the future. There will eventually be cross-platform end-to-end RCS encryption. For now, it's a proprietary Google Messages E2EE system and the current protocol is NOT being implemented by iOS but rather both Apple and Google are going to be implementing a new protocol.