Once Firefox will be able to handle https://theannoyingsite.com/ https://theannoyingsite.com/ properly, it will have achieved that. (I suggest opening the most

Once Firefox will be able to handle https://theannoyingsite.com/ https://theannoyingsite.com/ properly, it will have achieved that. (I suggest opening the most annoying site in incognito mode.) I had to tweak my Firefox quite a lot to pass that "benchmark".