Hello,
Sorry to hear you are having issues. This is strange, but I don't get scroll bar at all. And, from what I know if the list is taller than the display, the menu will automatically add another column on itself. Refer my screenshot below. Btw, I am on Start11 v2.49.3 Beta, not sure if this was changed recently, but if I remember correctly, this is how it has been for some time.

Thank you.
Basj,
Stardock Community Assistant.