From v13 onwards, a lot of the UI stuff is controlled in the themes that we edit within the application (rather than in code on the application servers).
Its documented in the UI Themes section of the "Studio Developer's Guide"
Thanks David. I think you are talking about the CSS theming that can be done in the admin console. Wouldn't any changes be strictly limited to CSS alone? For a simple example of what I'd like to accomplish: I would like to show on the page footer the hostname of the particular server the user us connected to. This is obfuscated when the users access the cluster via a load balancer device.