It turned out to be… Samsung Keyboard in the end, probably reinstalled itself after a system update.

I thought it’d be something like com.samsung.clipboardsaveservice, which was the culprit on my old phone, but it didn’t even exist on my new one.

From https://delta.chat/en/help#sealedsender

Does Delta Chat support “Sealed Sender”?

No, not yet.

The Signal messenger introduced “Sealed Sender” in 2018 to keep their server infrastructure ignorant of who is sending a message to a set of recipients. It is particularly important because the Signal server knows the mobile number of each account, which is usually associated with a passport identity.

Even if chatmail relays do not ask for any private data (including no phone numbers), it might still be worthwhile to protect relational metadata between addresses. We don’t foresee bigger problems in using random throw-away addresses for sealed sending but an implementation has not been agreed as a priority yet.

I’m using FlorisBoard :) Whatever is doing this it’s not Samsung Keyboard, it’s a separate package.

Signal won’t be able to protect you from Chat Control.

Delta Chat can be self-hosted.

Briar uses much more battery than everything else I’ve tried (which includes SimpleX but not XMPP).

I opted to install a game, fail.

I don’t remember ever getting anything to work in Bottles. PlayonLinux is much better (for any sort of app, not just games).

My phone does have a headphone jack, and I could listen to the radio on the stock ROM using the workaround you mentioned.

It says it supports “ONLY smartphones with Qualcomm Snapdragon”. Too bad…

Thanks for the detailed comment! I’m trying to build the app, but I’ve been unsuccessful so far… I have zero experience with this. I’ll try asking the maintainer.

It didn’t work…

Florisboard. Android keyboard, doesn’t have spell checking yet but I’ve been using it for years, you might not need autocorrect as much as you think! (Note for Samsung users: Samsung Keyboard keeps adding items to its clipboard history whether it’s default or not. Clipboard history is also accessible through Edge Panels. Your passwords might end up and sit there for a long time… you can use adb to disable com.samsung.android.app.clipboardedge and com.samsung.clipboardsaveservice.)

Delta Chat, for messaging. Sign-up is extremely easy using the default server, and I’ve convinced some of my contacts to join.

I suggest mega.io as replacement for OneDrive. I use it myself, and it has a desktop app like OneDrive’s.