FYI, the project they mention, "TheirTube", can be found here: https://www.their.tube/about
This article from Mozilla's is even worse, burying the link in the third paragraph instead of the first: https://foundation.mozilla.org/en/blog/step-inside-someone-e...
But at least it goes to https://their.tube. Engadget links to http://their-tube.com instead.