YouTube has this annoying nag screen asking you to sign in when you have JavaScript enabled (which you need, because not even the front page and search is working without it anymore). You can select "no, thanks," but that decision is (AFAIK) stored in a cookie, so you'll be nagged again if you delete their cookies. Which makes it pretty clear that the sole purpose of this screen is "leave our cookies alone and don't interfere with our user tracking."
So, how do I get rid of this nuisance? I'm using Firefox as my web browser.