Describe your concern

<div role="menu">
	<div role="group">
		<span role="menuitem">Item 1</span>
		<div role="group">
			<span role="menuitem">Item 2</span>
			<span role="menuitem">Item 3</span>
		</div>
	</div>
</div>

Per ARIA specs, the role="menu" accepts group as acc child only if one of the following is true:

• group with accessibility child menuitem
• group with accessibility child menuitemradio
• group with accessibility child menuitemcheckbox

but it's unclear whether a group containing another group (group > (or with generic intervening) group) is acceptable. As written, it appears to be allowed as long as the parent group has at least one accessible child menuitem, but I'm not sure if that was the intended meaning.