The rig runs the testing environment, and using the ENV variable provided loads the config data from Twitch on where to look for your extension. If you’re running your extension on localhost:8080, have you set that as the Testing Base URI in your extension settings? If you have, the next things to check would be go to the extension url and make sure it’s accessible to you and accept any invalid certificates. If you’ve done that, check the config settings in the rig to make sure that’s all correct, and the console on the dev rig for errors.