Xvkbd - different key strokes depending on qube

I successfully set up xvkbd for working on a touchscreen device (shiftbook 13mi), emulating a german keyboard. In dom0, this works great.

Working with other qubes, basic keys like characters, digits, and space work, too, but several characters don’t, e.g. z/y are exchanged, others like ‘<>,.-+’ are also located differently. This problem applies to all applications in this qube, e.g. it occurs in the terminal as well as in firefox consistently wrong.

So this looks like a keyboard layout problem, but I could not find a simple pattern. E.g., it’s not just like US/EN layout. To my limited understanding, xvkbd and it’s configuration run in dom0, so how and why is that translated in other qubes? Where would I look for configuration to tune?

Additional information:

  • Configuring EN layout (X11 in dom0 as well as xvkbd as well as X11 in app qubes) works.

  • Configuring X11 in dom0 and app qubes to DE and configuring xvkbd to EN has the following effect: the keyboard behaves like a DE keyboard in app qubes, but with wrong “keycaps”; i.e. pressing a key that on the german keyboard would e.g. be ‘ä’ produces an ‘ä’, but the keycap says what’s on the EN keyboard there.

  • By doing this, I was able to create a xvkbd config file with a mixed layout, i.e. combining EN keycaps with DE keystrokes; as a workaorund, that basically works for me, a few keys are missing, but at least one can type most.

  • So the problem seems to be what is sent over the GUI binding; I do not know how this works or where this could be configured, but somehow keycodes and associated key symbols seem to be mixed

Anyone any useful hints how to solve this?
Should I report this as a bug?

Thank you for help!