This video shows how a new, fan-made "Despecialized Edition" of Star Wars was created. It's an astonishing amount of work. As CinemaBlend explains,
The video you see above is dedicated to the creation of Star Wars: Despecialized - an amazing, fan-made, high definition cut of the originally theatrically released Star Wars trilogy, constructed using a number of different versions of the movie that have been released over the years. Credit for the creation of restoration goes to a user named Harmy from the OriginalTrilogy.com message boards, who has really put together something magnificent here. As you'll learn watching the featurette, the greatest resource for the project was the Star Wars Blu-ray box set that was released back in 2011 - but Harmy's version actually goes beyond that flawed professionally-made cut and creates something that's in many ways superior.