I am using twenty thirteen theme w child and I have the same problem.
Any fix out there yet?
When I built my “drop and drag” menu I used ( was suggested) the # to create a non clickable sub-menu. But now I am finding that all those sub-menus are clickable and goto a page that doesn’t exist.
I have tried a couple of browsers. I have added the “#” to a couple of the menu items to see that was the problem and nothing changed. I have purged cache. no changes.
Any ideas?