def create_user_context(self) -> str:
    """Creates a new user context.

    Returns:
    -------
        str: The ID of the created user context.
    """
    result = self.conn.execute(command_builder("browser.createUserContext", {}))
    return result["userContext"]

def get_user_contexts(self) -> List[str]:
    """Gets all user contexts.

    Returns:
    -------
        List[str]: A list of user context IDs.
    """
    result = self.conn.execute(command_builder("browser.getUserContexts", {}))
    return [context_info["userContext"] for context_info in result["userContexts"]]

def remove_user_context(self, user_context_id: str) -> None:
    """Removes a user context.

    Parameters:
    -----------
        user_context_id: The ID of the user context to remove.

    Raises:
    ------
        Exception: If the user context ID is "default" or does not exist.
    """
    params = {"userContext": user_context_id}
    self.conn.execute(command_builder("browser.removeUserContext", params))

def get_client_windows(self) -> List[ClientWindowInfo]:
    """Gets all client windows.

    Returns:
    -------
        List[ClientWindowInfo]: A list of client window information.
    """
    result = self.conn.execute(command_builder("browser.getClientWindows", {}))
    return [ClientWindowInfo.from_dict(window) for window in result["clientWindows"]]

def command_builder(method: str, params: Dict = None) -> Dict:
    """Build a command iterator to send to the BiDi protocol.

    Parameters:
    -----------
        method: The method to execute.
        params: The parameters to pass to the method. Default is None.

    Returns:
    --------
        The response from the command execution.
    """
    if params is None:
        params = {}

    command = {"method": method, "params": params}
    cmd = yield command
    return cmd

def test_get_client_windows(driver):
    """Test getting client windows."""
    client_windows = driver.browser.get_client_windows()

    assert client_windows is not None
    assert len(client_windows) > 0

    window_info = client_windows[0]
    assert isinstance(window_info, ClientWindowInfo)
    assert window_info.get_client_window() is not None
    assert window_info.get_state() is not None
    assert isinstance(window_info.get_state(), str)
    assert window_info.get_width() > 0
    assert window_info.get_height() > 0
    assert isinstance(window_info.is_active(), bool)
    assert window_info.get_x() > 0
    assert window_info.get_y() > 0