It's a catch 22 really - If adverts are modified or removed, the dom will reflect that. If you completely spoof that you effectively break the dom for everythin

It's a catch 22 really - If adverts are modified or removed, the dom will reflect that. If you completely spoof that you effectively break the dom for everything else. If you only spoof the advert's own properties, you can infer state from other inline elements. If you block domains you can check for their response on the client. If you proxy the incoming asset before it hits the browser and replace it's content is harder to detect client side but the ad provider will be able to see what happened and would most likely not display your modified content, taking you back to the conventional detection strategies.