def dark_mode_app(tmp_path_factory) -> Generator[AppHarness, None, None]:
    """Start DefaultDarkMode app at tmp_path via AppHarness.

    Args:
        tmp_path_factory: pytest tmp_path_factory fixture

    Yields:
        running AppHarness instance

    """
    with AppHarness.create(
        root=tmp_path_factory.mktemp("appearance_app"),
        app_source=DefaultDarkModeApp,
    ) as harness:
        assert harness.app_instance is not None, "app is not running"
        yield harness
Start DefaultDarkMode app at tmp_path via AppHarness.

    Args:
        tmp_path_factory: pytest tmp_path_factory fixture

    Yields:
        running AppHarness instance

    
tests/integration/tests_playwright/test_appearance.py