Hello,   I'm trying to create a js function using fetch to refresh my access_token but it doesn't work. Every time I get the below error:   Access to fetch at 'https://idfed.constantcontact.com/as/token.oauth2' from origin 'myUrl' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch the resource with CORS disabled.   I'm guessing this works on the backend only??   Please advise!   Thanks,   ... View more