I would love to see Luke with his intended blue lightsaber in this Revisited version. They only made it green because of the blue sky on tatooine.
Granted George Lucas has contradicted himself many times over the years with regards to Star Wars, so who knows what the real story is, but the one I heard was that George made the saber green in Jedi to make it clear it’s a different one to the one Luke lost on Bespin.
Then it would have been scripted like that, and there wouldn’t be trailers with a blue saber.
Well, I was curious about this, so I had a quick search and found this informative read. It might be that both reasons are true; it was changed both to stand out better against the blue sky and also to differentiate it from the one lost on Bespin: http://www.forcematerial.com/home/2016/10/23/the-real-reason-luke-skywalker-has-a-green-lightsaber