Exception at EnableCorsAttribute in CM

Question

We've setup Sitecore 10.1 in containers. A CORS error always occurs when loading the Experience Profile. The error happens on POST to /sitecore/api/ao/v1/contacts/search and also when saving a Sitecore Form, on a POST to /sitecore/api/ao/v1/contacts/search.

There are plenty of other POSTS throughout CM which work correctly. I do not see any error in the Sitecore log. The response body of the POST which fails contains below error. FYI I did not enable CORS as described in this answer and am not able to reproduce this issue with the same code on a local VM.

Does anyone know how to fix this?

Value cannot be null or an empty string.\r\nParameter name: origins","ExceptionType":"System.ArgumentException","StackTrace":"   
at System.Web.Http.Cors.EnableCorsAttribute..ctor(String origins, String headers, String methods, String exposedHeaders)\r\n   
at Sitecore.Services.Infrastructure.Cors.CorsPolicyProviderFactory.GetProviderFromOrigins(HttpRequestMessage request)\r\n   
at System.Web.Http.Cors.CorsMessageHandler.<GetCorsPolicyAsync>d__6.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n   
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n   
at System.Web.Http.Cors.CorsMessageHandler.<HandleCorsRequestAsync>d__3.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n   
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n   at System.Web.Http.Cors.CorsMessageHandler

Answer 1

Posting answer in case anyone else runs into this. I do not have Horizon setup, but my CM Dockerfile still copied some of its artifacts which caused this issue. Removing below lines from Dockerfile fixed it:

# Add horizon module
COPY --from=horizon_resources \module\cm\content \inetpub\wwwroot