...I am using an install of Portal with a federated+hosted server running on an Amazon EC2 server. I have constructed a web map with some map services using both an ESRI basemap and a custom basemap from an image service which is then shared as a web app configured with WAB. When I use the ESRI basemap, I can toggle my layers using the layer widget as normal. When I use my custom basemap, I cannot toggle those layers. I would like to use the custom basemap to achieve the level of detail that the ESRI basemaps do not permit. I've attached some screenshots of what is happening with each basemap...any help/ideas would be greatly appreciated!