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SignalR - CORS error

After updating SignalR my program started to fail with the following error message:

Access to XMLHttpRequest at 'http://localhost:22135/chat/negotiate?jwt=<removed the jwt key>' from origin 'http://localhost:53150' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: The value of the 'Access-Control-Allow-Origin' header in the response must not be the wildcard '*' when the request's credentials mode is 'include'. The credentials mode of requests initiated by the XMLHttpRequest is controlled by the withCredentials attribute.

To fix it I had to update the CORS policy by adding the AllowCredentials() method:

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