It seems that Facebook comes out with a new update or overhaul of its website every few months. You can tell, because all of your friends start complaining! But there's no need to get worked up about it if you have Social Fixer.
Social Fixer used to be called Better Facebook. It's a browser extension for Firefox, Chrome, Safari and Opera that allows you to tweak most of the features on your Facebook page.
You can hide posts you've already read, prevent Facebook from displaying your recent activity and receive notification when you've been unfriended. Want to reorganize the layout of your page, or even add a customized theme? It can do that too.
Perhaps best of all, Social Fixer enables you to block annoying ads. Keep in mind, though, that it can't change what other people see when they look at your profile.