Fixes https://github.com/MicrosoftDocs/azure-docs/issues/38401

Author: ggailey777

articles/azure-functions/functions-create-function-linux-custom-image.md

@@ -138,9 +138,8 @@ With the custom image running in a local Docker container, verify the function a
 
 ![Test the function app locally.](./media/functions-create-function-linux-custom-image/run-image-local-success.png)
 
-You can optionally test your function again, this time in the local container using the following URL:
-
-`http://localhost:8080/api/myhttptrigger?name=<yourname>`
+> [!NOTE]
+> At this point, when you try to call your specific HTTP function, you get an HTTP 401 error response. This is because your function runs in the local container as it would in Azure, which means that the function key is required. Because the container hasn't yet been published to a function app, there is no function key available. When you use Core Tools to publish your container, the function keys are shown to you. If you want to test your function running in the local container, you can change the [authorization key](functions-bindings-http-webhook.md#authorization-keys) to `anonymous`. 
 
 After you have verified the function app in the container, stop the execution. Now, you can push the custom image to your Docker Hub account.