For nested pages (parent/child/grandchild) etc the drop-downs are offset to the right by one tab-width. I mean in ALL menus I have seen so far, whether pages or posts.
A partial offset drop-down, perhaps enhanced by color as well, would preclude the last tab on a long navbar from going off the screen.
Is this a fixable issue? It certainly goes beyond what I can figure out, but also, at least for CMS-intensive sites, this must certainly have been noticed by others, perhaps even resolved. Any suggestions?