this.id = new DefaultProblemId(name, displayName, cloneGroup(SharedProblemGroup.generic()));
        return this;
    }

    @Override
    public InternalProblemBuilder id(String name, String displayName, ProblemGroup parent) {
        this.id = new DefaultProblemId(name, displayName, cloneGroup(parent));
        return this;
    }

    private static ProblemGroup cloneGroup(ProblemGroup original) {