The Salesforce connector allows Smart Flows to communicate with Salesforce and pull data out of it and attach the generated documents
Note: Before the Smart Flows 4.12.0 release, Smart Flows cross origin resource sharing used an "allow all" approach. As long as the URL was associated with the Connector URL, it would be allowed to access entities within Smart Flows and the connector. However, after the 4.12.0 release, URLs will require both enterprise name and the connector naming.
You are experiencing 403 errors or missing Smart Flows buttons in your Salesforce instance please refer to Why can't I connect to the server after upgrading to version 4.12 and Manually Allowlist a URL to resolve the related CORS issue.