OK, I read through several deep posts, primarily Btrfs Assistant 1.0 is coming, testers needed, and decided to try Snapper and btrfs-assistant. After studying the approach that used grub-btrfs, I decided that I currently do not have a strong use case for adding a snapshot to my grub menu, and being able to boot from it.
Instead, I just want to be able make snapshots of milestone system states, and then be able to restore to an earlier milestone if I mess something up, just from within the OS and not involving grub. (I might be confusing the capability of btrfs as a journaling file system with something like Clear Linux as a journaling OS.)
So after finally going back and reviewing the post by @FishMonkeh (I think it is about no. 229), I wondered if I could just follow the first steps and simply install snapper and btrfs-assistant, and forego everything after involving anything to do with grub-btrfs and the grub configuration (no support for booting off read-only snapshots.)
So I did that, and ran btrfs-assistant, and set up the basic settings, and then added a few snapshots, deleted, and restored to the earlier, and rebooted, and then decided to make a couple more snapshots and between the last two, I set Welcome to “Don’t show me anymore.” My naive theory was that I could then restore the original snapshot, and delete the later two, and Welcome should pop right up on reboot.
But that didn’t happen, so I assume that either the snapshot was not including everything on the system, and just a limited area, or that I needed to actually run btrfs-assistant as root, and not just with sudo, or that maybe the snapshots were currently just template entries (like a schema) and no system state was actually being recorded yet because it needed the grub-btrfs by design–maybe I misunderstood whether or not I should be able to use it without the grub configuration.
I will need to study the core btrfs man and snapper man pages, or just btrfs and relearn how it fundamentally works. (I used an earlier btrfs years ago with OpenSuse, (or maybe it was Fedora) and I had the basic ability to snapshot different system states, and restore them. But before I go down that path, I wonder if what I tried should work, and if so, I will try to work it through a little more–like what should I be targetting with the snapshot, to catch the whole system? (I realize the first one would be pretty big, but all the others after that should be deltas, right?)
Cheers!