When you create an external auth identity provider, the callback URL is constructed using the org’s My Domain name.
- External Auth Identity Provider Callback URL Uses My Domain
When you create an external auth identity provider, a callback URL is generated for the external system to redirect back to. Now, the callback URL is constructed by using the org’s My Domain name. Instead of the URL https://login.salesforce.com/services/extidp/callback, the callback URL is now https://<my_domain_name>/services/extidp/callback. If the external auth identity provider is associated with a managed package, then the callback URL is constructed by using the package namespace.