I want to exchange information with BigCommerce during application installation and send POST request for code from html page. But I keep getting blocked by CORS: \" No \'Ac
We do not support CORS. It is very insecure to try to call the API from javascript on in the browser directly. This exposes an API token which enables someone to have access to any data in the store available through basic authentication. This would include PII.
If you really need to call info from the API, please use a secure web service that returns very specific values to your script as opposed to calling it directly.