You can totally back up and export your Signal messages on Android. You export to a file (encrypted with a generated pin), copy that file to a new device, and import that file into Signal. I've done it several times and have never lost a message.
And I don't want it only as an encrypted blob to bring back into Signal though of course that option should be available. I would actually like the abilityt o export it in a format of my choosing.
I don't think so. At some point I setup my Signal to send backups to (I think) the "/Signal/Backups2" directory on my phone. My phone doesn't support SD cards, so there may be some quirk with those, but I definitely had some control.
> And I don't want it only as an encrypted blob to bring back into Signal though of course that option should be available. I would actually like the abilityt o export it in a format of my choosing.
That's a nice to have, but it's totally reasonable for them not to support a bunch of random formats someone might like, but hardly anyone would ever use.
If you want a different format, just write a converter. It wouldn't be very hard. The backup is literally an encrypted SQLite DB, and there's a command-line decryptor available (if you have your key).
The backup is literally an encrypted SQLite DB
I know this, but they don't exactly make any effort to tell you. While I agree that they can't support every possible format they could certainly offer CSV, JSON, and SQLite.