It come from a bug crashing kcm_mouse, all details here. https://bugs.kde.org/show_bug.cgi?id=482048 The bug will be fixed in plasma-desktop 6.0.2 but that will lead to the problem no mouse/touchpad backend can be found if X flag is not enabled when building the package. I'm not expecting every user would be an expert configuring the package to work with X11, but is it possible to enable this flag by default for this ebuild. Not doing that will just lead to no mouse/touchpad backend found on your computer for most users.
X USE is enabled in desktop profile make.defaults. Are you not using a desktop profile?
...but also I don't see where this particular change you linked relates to X.
(In reply to Andreas Sturmlechner from comment #1) > X USE is enabled in desktop profile make.defaults. Are you not using a > desktop profile? Yes I'm using a desktop profile. I didn't get the issue in KDE5 because plasma-desktop-5.x depends on a couple of X11 libraries. Take note there is not X flag in plasma-desktop-5.x When I upgraded to KDE6, I didn't saw the new X flag for this package. Without knowing what, came a bug I found in plasma-desktop. They fixed the bug upstream but dev guy over there told me some distro don't compile plasma-desktop with X enabled. I doubled checked and I found that is the case for Gentoo. Not enabling X by default is no big drama but will lead to no backend found for mouse and touchpad on kcm_mouse when running KDE6 under X11 hat. Wayland should be spared but like probably a lot of people, I'm not using it.
I just told you that desktop profile has X *enabled by default* and you simply ignore that? Show us emerge --info or this bug will be simply closed by tomorrow.
