Hi Jens,
could we try and separate recipes for WindowManager and HomeScreen? As far as I've understood from your recent commits, we're not going to use wl-shell-emulator.so (that is in /usr/AGL/CES2017/weston.ini.ivi-shell) any more. That probably means (correct me if I'm wrong) that all graphic applications will need WindowManager to run, not just HomeScreen.
I'm particularly interested in mantaining openivi-html5 alternative home screen which is also a part of agl-sota demo at CES2017. It will require WindowManager, but will definitely conflict with HomeScreen.