def test_extra_overlay(driver: WebDriver, extra_overlay: AppHarness):
    """Test the ExtraOverlay app.

    Args:
        driver: WebDriver instance.
        extra_overlay: harness for the ExtraOverlay app.
    """
    # Check that the text is displayed.
    text = driver.find_element(By.XPATH, "//*[contains(text(), 'Hello World')]")
    assert text
    assert text.text == "Hello World"

    time = driver.find_element(By.TAG_NAME, "time")
    assert time
    assert time.text
Test the ExtraOverlay app.

    Args:
        driver: WebDriver instance.
        extra_overlay: harness for the ExtraOverlay app.
    
tests/integration/test_extra_overlay_function.py