CORS Request Block - Same Origin Policy

[BarryCarlyon]

@KJ_Keys

The error received when pressing one of my buttons is:
Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at http://localhost:3000/words. (Reason: CORS request did not succeed). Status code: (null).

Your server serving the HTML/JS/CSS to be embedded in the iframe on Twitch has it’s own CSP headers preventing communications.

see also

Twitch Extensions Part 6 – Dev Environment Updates – Content Security Policy!

New Extensions policy for Content Security Policy (CSP) directives and timeline for enforcement

Update (2022-01-24) In order to minimize disruption and accommodate recent Extension reviews, we have made a few updates to how and when the CSP policy will be enforced this week. The CSP enforcement date has been moved by two days to Thursday, January 27 and should begin sometime between 11am-12pm PST. If you have submitted an Extension review request before January 25 at 12pm PST, your Extension will continue to function without the new CSP enforcement until the review has been completed. W…

The errors suggests the problem is not your EBS but in the FrontEnd server.