Keyboard Setting switched from German to English (xfce, twm, icewm) no way to set back

My keyboard setting in xfce (same in twm and icewm) switched to english after a restart of the notebook (HP ZBook 15 G2 A30). Locale settings are still German, and console by ctrl-alt-f7 still has gernan keyboard. Plasma has it, too.

Actually english keyboard settings on a german keyboard are annoying, any way to switch it back? My suspicion is that it is some window manager default as plasma is using KWin while xfce etc use Xfwm4. But I did not find where to set it. None of the settings inside xfce has any effect.

Did you check here in Xfce4?
https://docs.xfce.org/xfce/xfce4-settings/keyboard#layout

I did. unchecked system defaults, set to German, no effect. Thanks for the hint though.

I found a workaround: When typing “setxkbmap de” in a terminal window after every xfce4 session login, the keyboard settings are ok for that session. I can live with but still curious why that change came over me. I have a working xfce4 on 3 other boxes without such stuff.