For those looking for similar answers, I did some additional testing and will share my conclusions below.
Summary: The latest distros with Plasma 6 and Wayland are workable, but I experienced interface and stability problems outside of my comfort zone.
Mixing HiDPI displays with lower-res ones generally asks for independent scaling, which is only possible with Wayland. Wayland does not support drawing tablets as well as X-11. While I say that, if I had to work in Krita under Wayland, I could probably do that, at the cost of some convenience that the Wacom drivers offer under X-11 (switching pen button functions, switching active screen with a shortcut are hard or impossible under Wayland+Plasma)
NOTE: The huge problems with tablet cursor not moving which I mentioned above were all caused by the virtual machine (KVM/QEMU). Turns out, KVM does not know how to interpret the tablet pen for the VM guest, even if the drivers are loaded.
I had to install and test everything on bare metal, and in some cases (Manjaro, Tumbleweed) had to be installed on a HD before I was able to switch to Wayland session (X-11 was default with live session).
Some findings:
- All the Plasma 6.x distros I tried showed incorrect cursors outside of Krita and Firefox (showing crosshairs when using tablet pen)
- Fedora KDE spin only comes with Wayland, so there’s no fallback to X11. I would avoid that distro for Krita right now.
- Ubuntu 24.10 (GNOME) appears to have good support for Wacom, but I experienced freezes in the interface where both tablet and mouse would stop working and I had to do hard resets. I don’t know if it was because I was using it as live session (without installing), but I was super unhappy with having to use GNOME.
- Kubuntu 24.10 had some interface quirks that caused me to try rolling distros instead, in hope those issues would be solved faster.
- Tumbleweed KDE looked quite promising but I also experienced weird behaviors that would make me feel uncomfortable if this were my production machine - maybe it was the Plasma 6.2 (example: tablet pen cursor would not work on some system menus, mouse did)
- Manjaro KDE felt like the most polished experience with Plasma 6.1 + Wayland. It was definitely workable and I would probably go with Manjaro if I had to switch distros. [edit] Brushes that use pen rotation worked great as well, just so you know.
- I was unhappy with how Krita looked on scaled screens (the 4K screen would have to be scaled up to match the others, so it would defeat the purpose of using it as primary display)
I hope this will help someone. Again, things in Linux sometimes move fast, and sometimes get stale. Wayland shows promise, and if you’re willing to compromise, it can definitely be used with Krita and a drawing tablet.