https://community.bistudio.com/wiki/Resource.cpp/bin
To reiterate what is stated there, UI elements are very polluting in configs and would probably benefit from being in a separate namespace from configFile, similar to missionConfigFile and campaignConfigFile. Of course this poses the issue of backwards compatibility, but with the recent addition of import I believe it might be doable, moving the current UI configs to resource namespace, and then importing them for backwards compatibility. Addons can then move over to the new namespace at their own pace.
This is something that should've of course been done sooner in development, but better late than never.