Use this little website to test if a URL is setup correctly to work with CORS.
Shareable link: https://cors-test.codehappy.dev/?method=get&origin=https%3A%2F%2Fcors-test.codehappy.dev%2F&url=https%3A%2F%2Fmicro.blog%2Findieauth%2Fauth
It does not have the access-control-allow-origin header set to *. Without this header, requests from other domains cannot be made to it via a users browser.
If you have access to the server for the URL, you'll need to modify it to add the access-control-allow-origin header. If you do not have access, you'll need to upload the file somewhere else.
These are the response headers received when making the request.
cf-cache-status: DYNAMIC
cf-ray: a2c9f1b8ec41e88e-CMH
connection: close
content-type: text/html;charset=utf-8
date: Mon, 17 Aug 2026 16:09:37 GMT
server: cloudflare
transfer-encoding: chunked
vary: accept-encoding
CORS tester was built by @mscccc. The code is available on GitHub. Sponsored by HTML/CSS to Image.