Plasma 6 and "alternative" x11 input drivers

[dmpogo]

Just for clarification, I am trying to understand how Plasma 6 deals with X11 where input devices are not driven by libinput
I have a Lenovo laptop with mousy buttons and touchpad (and that IBM red stick). Keyboard, buttons and stick are driven by evdev, while touchpad is driven by synaptic.

In Plasma 6 settings what I have

1) Keyboard setting appear normally
2) Mouse settings are blank
3) Touchpad settings say 'touchpad is not found, please connect external'

All devices work fine (though touchpad X11 settings now required explicit parameter set to make Tap work as first button, which it did not need before)

Now, 2) is probably related to KCM problem widely discussed now on KDE bug list https://bugs.kde.org/show_bug.cgi?id=488326
But 3), should I expect my touchpad be detected ? I honestly do not remember how it was for plasma-5