Tried to find out how to create ToggleButton in Splitties, and the only way I've found is view(::ToggleButton). That is not so common widget, so I guess it is OK. But the question is with basic samples:

val launchDemoBtn = button {
    textResource = R.string.go_to_the_demo
}

It doesn't work for me - just empty space is shown, and no errors. I didn't notice this initially because I started right from AppCompat samples (they work pretty well :))

Empty space is Susan l shown instead of the view? Can you check the layout parameters? Defaults to match contraints in ConstraintLayout FYI, so could be shrinked to zero if not constraints to expand.

I dig deeper and found that actually that is because of styles - there is an exception "This component requires that you specify a valid TextAppearance attribute. Update your app theme to inherit from Theme.MaterialComponents (or a descendant)."