I don't know if it's a problem for you, but the following "custom control" code compiles with Java 8u20, but does not compile with 8u40 b17.

It says: "getUserAgentStylesheet() in MyTextField clashes with getUserAgentStylesheet() in Region. Attempting to assign weaker access privileges (protected), was public".

Seems like you changed it from protected to public.

I am ok with it, if it was necessary, but I am not sure, how strict your backwards-compatibility policy is in such a case. I guess it won't harm runtime behavior(?).
Otherwise feel free to close this bug.


    public class MyCustomControl extends Control {

        @Override
        protected String getUserAgentStylesheet() {
            return "";
        }
    }