Kayboard layout configured at:
System Settings > Input Devices > Keyboard > Layout
is not applied to X11 applications.

For example, when I add jp layout into the list, on Wayland applications, the
layout become jp, but on X11 applications (e.g., xterm, vscode), the layout
remains US.

Here is output of xkb_keymap:

```
xkb_keymap {
        xkb_keycodes  { include "evdev+aliases(qwerty)" };
        xkb_types     { include "complete"      };
        xkb_compat    { include "complete"      };
        xkb_symbols   { include "pc+us+inet(evdev)"     };
        xkb_geometry  { include "pc(pc105)"     };
};
```

Workaround:
Run the following command
$ setxkbmap jp

* Plasma 5.27.11
* IBus 1.5.28 (which does not control key layouts on Wayland anymore)