Originally posted by Dave
The reason it becomes blurry is because they have it set so that their pop-up which says 'login with your youtube account' reduces the opacity of the main page so as to make it stand out. In other words, if there's one thing for you to worry about it's not the text being blurry :p.
NGS is partnered with a sub network of Fullscreen like CreatorX and I'm pretty sure they all link YouTube accounts to verify no stikes etc before they consider for partnership.
Nothing to worry about as it's common practice and they don't have control of your account.