This is a free and open-source web proxy that can unblock websites. FilterBypass can be used to unblock sites like YouTube, Facebook, Twitter, VK, and many more. It provides access to many online websites without having to type the URL each time.

In order to use this addon, you first need to download it from the Chrome Web Store. 

You can unblock sites by adding the domain name of the site you want to unblock and the FilterBypass domain to the addon. You can also switch the proxy on and off with a single click when needed.