return getProjectSelectors(pa -> pa.optional() && pa.active());
    }

    /**
     * @return Required inactive project selectors, never {@code null}.
     */
    public Set<String> getRequiredInactiveProjectSelectors() {
        return getProjectSelectors(pa -> !pa.optional() && !pa.active());
    }

    /**
     * @return Optional inactive project selectors, never {@code null}.
     */