Backwards compatibility broken: Why was Color made final

[Randahl Fink Isaksen]

After upgrading to FX8, the framework I have been developing since the early access release of JavaFX three years ago is now broken. 

My framework has some really cool features for working with color, which relies on our own class PaletteColor which extends javafx.scene.paint.Color.

Why would you, after three years, make the Color class final, thereby breaking backwards compatibility?

I would really like to know the thoughts behind that decision.

Yours

Randahl