If DropDownMenuItem is first item below SectionMenuItem, menu does not work

Description

If a DropDownMenuItem is the first menu item below a SectionMenuItem, it does not select when viewing from other parts of the UI.

Steps to reproduce

1. Use this code:

using System.Collections.Generic;
using EPiServer.Shell.Navigation;
 
namespace MenuBug
{
    [MenuProvider]
    public class MenuBugExample : IMenuProvider
    {
        public const string MenuWaffleMenu = "/global/newwafflemenuitem";
        public const string MenuDropDownTopLevelMenu = "/global/newwafflemenuitem/example";
 
        public IEnumerable<MenuItem> GetMenuItems()
        {
            // use for sub menu item off CMS
            return new MenuItem[]
            {
                new SectionMenuItem("New waffle menu item", MenuWaffleMenu) {IsAvailable = (_) => true},
                new DropDownMenuItem("Example dropdown", MenuDropDownTopLevelMenu) {IsAvailable = (_) => true, SortIndex = 100},
                new UrlMenuItem("Clickable menu item", MenuDropDownTopLevelMenu + "/menu item", "/episerver")
            };
        }
    }
}

2. Browse to the CMS.
3. Try and select the "New waffle menu item" menu item.

Expected
Select the first menu within the hierarchy that has a URL.

Actual
No menu is selected.