Impossible to mix as in impossible to wait on mixed inproc/server objects, and we have to fallback to wineserver if any object type of the objects waited on is unimplemented,
Or impossible in every use case, and every object type has to be implemented before any of this can work?
If this is the latter, what happens if any new object type needs to be added in the future? Does it block any server-side implementation until there is support for it in the kernel?