Anything that helps the web export progress sounds like a good idea to me, I think there’s a lot of potential in that feature.

Being able to play game demos in the browser before installing the full version if you like it would be nice.

But for developers themselves I think it would be really cool to see the output of the tutorial you’re following before you start. It would be pretty motivating to see what’s coming and I think it could help get across some of the concepts which can be difficult in game dev.