It was fairly easy. I used rustic to back up my entire home directory to a USB flash drive.
The trick is to ensure that all applications (except KDE) are closed. Firefox, for example, really hates if you try to actively sync or copy over it's profile directories while it is running.
And then I also nuked my podman user data. (podman system reset). Podman sometimes makes the ownership of it's files weird, but also the container images take up a lot of space that I don't really care about actually backing up. It's okay if those aren't on the new laptop.
Then I backed up to the usb flash drive:
rustic init -r /path/to/repo — this will prompt you for a password
rustic backup -r /path/to/repo /home/moonpie
One cool thing about the backups is that they are deduplicated and compressed. So I backed up 120 gb of data, but it was compressed to 80 gb.
restic snapshots -r /path/to/repo
The snapshots are deduplicated as well. Data that doesn't change between snapshot versions, doesn't take up any extra space.
rustic restore -r /path/to/repo snapshotid /
The / is needed because rustic restores to paths underneath the thing. It gave me a bunch of permission errors about not being able to read stuff not in my home directory, but eventually it restored all of my data.
And then yeah. All my data. Except Wifi passwords, which I had stored as unencrypted for all users, because I didn't like having to unlock the KDE wallet to get to Wifi passwords when connecting. I had (and have) LUKS encryption so I didn't worry about that too much. But it means that data not in my home directory was not copied over.
It was surprisingly smooth, and now I have all my data and firefox profiles and stuff on the new machine.
No. Telegram is not end to end encrypted, by default. Their encryption is only in certain versions of the app. And finally, it's a custom protocol that has never been seriously audited.
Signal doesn't claim they don't share, they claim they can't share the private messages, which is true because it's open source and we can see how the encryption works, and we also know that signa's encryption is always on.
Edit: well, I guess is private messages refers only to "secret" chats encrypted by telegrams end to end encryption, and assuming that their custom encryption isn't backdoored then yes, I guess this claim is true.
But telegram chats are not "secret" by default. It must be explicitly enabled per chat.