How to add subitem of a MenuGroup in MyAccount

var myaccountmenu = container.getComponent("MyAccountMenu");
var preordersviewall = {
 id: "preordersviewall",
 groupid: "preorders",
 name: "View All",
 index: 1,
 url: "preorders-view",
 permissionoperator: "OR",
 permission: [
     {
         group: "transactions",
         id: "tranSalesOrd",
         level: "1"
     },
     {
         group: "transactions",
         id: "tranEstimate",
         level: "1"
     }
 ]
}

myaccountmenu.addGroupEntry(preordersviewall);

In the following example, a menu item is added as the first subitem of the menu group with the id preorders. The menu item points to a landing page called preorders-view. To view the menu item, the user must have either of the two permissions specified in the permission property.