[mjMenuTriggerFor]: opens an mj-menu from the element it sits on, usually a mjButton. Built on the CDK
menu: the trigger carries aria-haspopup, aria-expanded and aria-controls, a click or the arrow keys open the
menu, Escape and a click outside close it, and focus returns to the trigger.
[mjMenuTriggerFor]: opens anmj-menufrom the element it sits on, usually amjButton. Built on the CDK menu: the trigger carriesaria-haspopup,aria-expandedandaria-controls, a click or the arrow keys open the menu, Escape and a click outside close it, and focus returns to the trigger.Example