Hey, good questions. I am writing this one as a reference thread since questions like this could come up a lot. Sorry about the time investment in reading this drivel.
NOTE: why butterknife at all? The reason to pick butterknife over a vanilla Debian forky live ISO is the btrfs + timeshift + grub-btrfs stack, configured out of the box. Coming from Spiral you’ll recognize the idea: snapshot-aware Debian, just with timeshift instead of snapper. If you don’t want that stack, a Debian forky netinst gets you to KDE in fewer steps and questions 1 and 2 below mostly evaporate.
1. Falling back to plain Debian
Nothing to do. butterknife is just upstream Debian Trixie from deb.debian.org. No Butterbian repos, no pinning, no patched packages. If I get hit by a bus tomorrow, your box keeps pulling Debian security updates like any other Debian box.
The Butterbian-flavored bits are tiny and optional: a first-login WM picker that disables itself after one run, a lightdm theme, and (if you went btrfs) a timeshift + grub-btrfs apt hook you’d probably want to keep anyway.
2.Switching to forky (testing)
Standard Debian move. Edit /etc/apt/sources.list, swap trixie for forky, then apt update && apt full-upgrade. Few things to watch:
- Drop the trixie-backports line. Backports doesn’t exist for testing.
- trixie-security becomes forky-security.
- Keep non-free-firmware if you needed firmware to boot.
If you went btrfs at install, the apt pre-invoke snapshot hook is your best friend on testing. When something breaks (and on testing it will, occasionally), roll back from the GRUB snapshot menu and get on with your day.
3. KDE
KDE is a big package set, so every apt run is going to make timeshift snapshot a lot of bytes. Not broken, just be aware.
If you want a pre-themed DE with the snapshot stack already wired up, Butterbian-XFCE might be the closer fit: install XFCE, then apt install kde-plasma-desktop on top and pick Plasma at the lightdm session menu. You get both DEs side by side and only paid for the snapshot setup once.
Going the butterknife route anyway: hit 0 at the WM picker to skip, then from the console pick a rung:
sudo apt install kde-plasma-desktop # minimal plasma
sudo apt install kde-standard # plasma + the usual KDE apps
sudo apt install kde-full # the kitchen sink (gimp, firefox, etc.)
sudo apt install task-kde-desktop # Debian's curated task package
Reboot, log in via lightdm. Want sddm instead? apt install sddm and dpkg will offer to switch.
Just my random thoughts. None of this is a wrong answer, depends what you’re after.