Demo fails with either library

[dandv]

Both fail with uBlock Origin disabled as well.

[wbobeirne]

Looks like you're hitting CORS errors. I recently had to add origin checking since someone was abusing the infura API key and using up the request limit. I'm personally not seeing this in production (works fine for me) and Infura stats say that there are still pretty regular requests hitting this. Can you make sure that your origin header is being sent properly?

[hippolyte42]

Experiencing the same issue.