We have encountered a strange menu behavior with Safari (Mac) and Chrome (PC). Clients have complained about this and we were able to reproduce it:
Please go to http://www.prgn.com and select “members” from main menu. On “Europe” try to go further down than “Spain” -> *pow* menu disappears.
Or try to get past “Massachusetts” under the “North America” entry. Same thing.
With Firefox everything’s OK, with Chrome on PC (not on Mac) the menu disappears. With Safari on a Mac the menu disappears as well.