Just a note from playing with the EA build. Minimal example:

import java.util.ArrayList;

value class HittableList2 {
    private final ArrayList<Object> objects
            = new ArrayList<>();

    HittableList2() {}

    HittableList2(Object object) {
        add(object);
    }

    void add(Object object) {
        objects.add(object);
    }
}

This gives the error

/Users/<username>/Development/raytracer/src/HittableList2.java:10: error: cannot reference add(Object) before constructor has been called
        add(object);
        ^

I know this means the superclass's constructor (and that I need to put an explicit super() at the top of the method), but reading that straight "cannot reference ... before constructor has been called - I'm in the constructor!"