I'm not familiar with rolling ads. Do you mean the page keeps reloading itself to show different things? Next time you see it, could you check the message language in more detail: if it says Firefox stopped the page from reloading or redirecting, you might have accidentally turned on an accessibility feature. To turn off the redirect block, you can use the Advanced panel of the Options page: "3-bar" menu button (or Tools menu) > Options > Advanced On the General mini-tab, in the Accessibility section, uncheck the box for "Warn me when websites try to redirect or reload the page" Does that fix it?