Page loading issues in the browser-based user interfaces
When users encounter page loading issues in one of the Tridion browser-based applications, a number of issues could be the cause. For some, it is possible to identify the cause of the issue by examining the developer tools of the browser.
Request blocked by CORS policy
The error indicates a requested resource is blocked by the CORS (Cross-Origin Resource Sharing). In Chrome, you will see an error similar to the following:
This can occur when the application is secured using Access Management, but the requested URL does not match any redirect URL that is configured in Access Management.
To resolve this issue, open Access Management and go to the Applications list. Check that redirect URLs that are defined for the application, and correct as needed.