OK, OK, please forget that I told that I have to press alt+ctrl to change from US to HU layout in sddm. The truth is that as soon as I press ANY key, sddm-s keyboard layout indicator (which is a flag) immediately changes to Hungarian, so sddm seems to honor /etc/X11/xorg.conf.d/00-keyboard.conf, but it misinforms me before the first keystroke. I tried kdm too, and it also lets me log in using Hungarian keyboard layout, which is fine. So, after running `localectl set-x11-keymap hu` everything seems to be fine except that sddm initially displays a US flag instead of HU. BTW, am I right when I thing that /etc/X11/xorg.conf.d/00-keyboard.conf was created by localectl? Interestingly, I didn't see it in the strace output.