Which project has a good interactive tutorials on its website?
For me, Svelte is the winner so far:
https://svelte.dev/tutorial/basics
Not sure if your ask is only for open source. I got lucky that my product is JavaScript based and Docusaurus is a perfect way for me to have live interactive docs by using MDX and a wrapper react component. https://sqlframes.com/docs and a quick 5 minute tutorial at https://sqlframes.com/tutorial .