I’d think so. The popup usually locks up your screen until you deal with it. If you can exit the screen by closing the tab, it should be okay.
I don’t know... Google and facebook scripts follow you around until you actually clear your cache. They don’t even go away if you shut down your computer. As soon as you fire up and start your browser they are back. All of these take advantage of the “remember me” cache option.
As inconvenient as it might be... I think we are all going to be forced to set our browsers to “clear all cookies” every time we shut them down.