I do not know why, nor how to stop it, but Google "adsense" ads are popping up every time I open a page or site that contains advertising. It apparently works like this.
If you do a search for a product, and then open any sites, or perhaps rather sites that have subscribed to adsense, that site pops up in place of another ad. I went through the process to disable it, and a page opened showing it had been disabled with a "button" to enable it again should I decide to do so.
I closed the page without clicking on the enable button, I assumed leaving it disabled. Still the ads pop up. It is more annoying than opening AOL and them trying to sell you one of their "services". At least that only happens when you first open the site, not everytime you open another site or page.
I destest it when some intruder tries to take over my computer, be it toolbars, or my homepage.
Off the soapbox.......................................................for now.