Fly-out menus - use button as toggle - functionality doesn't match text description in example

[kospl]

https://www.w3.org/WAI/tutorials/menus/flyout/#use-button-as-toggle

The invisible label of the button is set to “show submenu” or “hide submenu”, reflecting the state of the submenu.

this is happened not to be true, button label is always show submenu for “Space Bears”.

Not sure if this label for dropdown button have to be changed as a best practice here, but currently it's not changing, and documentation may need to be updated.