hope you can help as i've been trying to fix this for a couple of hours:
I recently updates the main twentytwelve theme and have since (i believe at least, been a while since i had worked on the project) non-working sub-menus.
Whenever i hover over a mainmenu entry with submenus i'm getting a scrollbar to the right with almost inaccessible submenu-entries (tested on opera/firefox linux and firefox windows).
I've tried changing css for
main-navigation ul li:hover and such with no change.
Has anybody seen the same behavior elsewhere and how can i fix it?