It's true that it's a good class. Rather than making something right away with it, you can intuitively see the difference between using pure js and vue.js. However, it's too troublesome and difficult to practice in a Windows environment other than a Mac environment... I think there's not much consideration for that. I would have known if they had left it in a notice or an explanation somewhere, but I was struggling on my own and found it through Q&A.