testBlock.setExtendedSecurity(true);
            assertTrue(testBlock.isExtendedSecurity());
        }

        @Test
        @DisplayName("Test expiration property")
        void testExpirationProperty() {
            assertNull(testBlock.getExpiration());
            testBlock.setExpiration(123456789L);
            assertEquals(123456789L, testBlock.getExpiration());
        }
    }

    @Nested