DEMO is broken

[Zirafnik]

All 5 examples fail.

Tested on both Firefox and Chrome.

Demo link: https://node-cors-client.netlify.app/

[one2code]

I've looked over the code related to this issue, both on the server and client side. I've found this to be the problem, and it is related to Heroku removing their free tier.
The HTTP request methods such as GET, HEAD, POST, DELETE are being made with this url https://node-cors-server.herokuapp.com/simple-cors which is now a dead link. When loading the URL, it returns this

In conclusion, this issue should probably be closed, and perhaps a separate issue opened to recreate the HTTP method requests on Netlify.