The initiative to make the Wayland session in KDE suitable for everyday use, which started almost four years ago, has been successful in the last year. Even on NVIDIA’s proprietary drivers, everything finally worked smoothly.
Well, almost.
After waking up the PC from sleep mode (S3, also known as «suspend-to-RAM»), the screen was completely littered with artifacts. It turned out that this behavior is well documented, and the fix is quite trivial:
echo 'options nvidia NVreg_PreserveVideoMemoryAllocations=1' > /etc/modprobe.d/nvidia-power-management.conf
systemctl enable nvidia-suspend
After reboot all the image artifacts disappeared.