The Gnome Help zenity manual explains:

An access key is a key that enables you to perform an action from the keyboard rather than use the mouse to choose a command from a menu or dialog. Each access key is identified by an underlined letter on a menu or dialog option. Some Zenity dialogs support the use of access keys.

I tried to use this feature with several Zenity dialogues but I had no success. A MWE:

zenity --list --column "Item" "Apples"\ "Oranges"\ "Pears"

Adding an underscore (e.g. "_Apples") as explained by the Help page the Access Key does not seem to work.

Question: the manual says that "some Zenity dialogs" support this feature. Which dialogues? I tried several dialogues but I failed. Thanks a lot.