If the address bar is hidden using UI Autohide, when I go to make a selection from the address bar using the dropdown arrow, the whole list disappears when I move my mouse vertically down to make a selection. It basically disappears once the cursor moves beyond the vivaldi menu interface. As soon as the mouse cursor moves over the web page itself, the whole address dropdown disappears before a selection can be made.
It should be noted that the same behavior does not exist when I use the dropdown for the search box which is located beside the address bar.