Adds an item with the specified title to the end of the menu.
- macOS 10.0+
The title of the new menu item. If an item with the same title already exists in the menu, the existing item is removed and the new one is added.
The menu item uses the pop-up button’s default action and target, but you can change these using the setAction: and setTarget: methods of the corresponding
Because this method searches for duplicate items, it should not be used if you are adding an item to an already populated menu with more than a few hundred items. In a situation like this, add items directly to the button's menu instead.