The topic has been discussed to death on the "Suggestions and User Assistance" forum. It's not a pop up "ad" but a new feature of Bike Forums. All browsers will show it. If you are logged in 24/7 you'll never see it. I only log in if I'm posting or looking at photos so I see it all the time. Only a minor annoyance on my desktop until I minimize it. More of an annoyance on my mobile device where it takes a careful aim to hit the minimize button with my pudgy fingers. Often I'll hit the ad behind it and then have to close that. Sometimes it will obscure the log in window which it is intended to encourage.