The following Window properties use NonBindableDoubleProperty, a subclass of DoublePropertyBase, which throws a RuntimeException on an attempt to bind to them.

x, y, width, height

The user has no compile-time way of knowing this, since the public *Property() methods return a DoubleProperty object.

Additionally, the following Stage attributes use an ordinary BooleanProperty:

fullScreen, iconified

These must be made non-bindable (see RT-16087). Rather than extending the pattern of using an internal NonBindable* class to enforce non-bindability at runtime, we should use the pattern of making these ReadOnlyProperty objects, even though they also have a corresponding set method. Note that this also will prevent directly animating these properties (which doesn't make sense for someone to do anyway).