Get the menu binded to menubutton and you can do anything with this menu.
Code:
var opts = $('#mb').menubutton('options'); // the menubutton options
var m = $(opts.menu); // the menu object
var item = m.menu('findItem', 'Copy'); // find the menu item
m.menu('disableItem', item.target); // disable the specified menu item
How does 'findItem' work? what do I need to put in the 2nd parameter for it to find the right menu?
Is it possible to use 'findItem' by giving it an object that I have in my system that is attached to the menu item?