I'm new to Salesforce, but before asking I've been through docs and can't find a way around it.
I have a Salesforce Developer Edition where I have a user with API privileges, connected app added and CORS set up, but whenever I try to authenticate user from my app (run locally) I get:
XMLHttpRequest cannot load https://login.salesforce.com/services/oauth2/token. Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'https://proj.loc:1337' is therefore not allowed access. The response had HTTP status code 400.
What can be the issue here? Is it possible, that the fact I have a self-signed certificate on my localhost is blocking authentication?