.NET Core/6: Prevent .NET runtime from logging errors that are already handled in ExceptionFilter

We use Graylog to log everything, on Windows machines we also log into EventLog. I recently noticed for every exception I got two items in EventViewer, one is Logged by our code, and the other is logged by the .net runtime I guess. It is a little bit annoying. TLDR; here's the answer:

        public override void OnException(ExceptionContext actionExecutedContext)
            actionExecutedContext.ExceptionHandled = true;
            actionExecutedContext.HttpContext.Response.StatusCode = StatusCodes.Status500InternalServerError;
            actionExecutedContext.Result = new ObjectResult(new ErrorResponse()
                StatusCode = (HttpStatusCode) StatusCodes.Status500InternalServerError,
                Message = actionExecutedContext.Exception.Message,

The key is this line actionExecutedContext.ExceptionHandled = true;. Reference