}

    @Test
    void testPropertiesClear() {
        // Test for issue #11552: NullPointerException when clearing properties
        Model model = new Model();
        model.addProperty("key1", "value1");
        model.addProperty("key2", "value2");
        assertEquals(2, model.getProperties().size());

        // This should not throw NullPointerException
        model.getProperties().clear();