Made a mistake pasting the link in the OP. It was:
https://opensprinkler.freshdesk.com/support/solutions/articles/5000164006-using-a-different-server-for-ui-assets
I found the document. Same name but different URL…
https://openthings.freshdesk.com/support/solutions/articles/5000164006-using-a-different-server-for-ui-assets
What else does the controller rely on the internet for? If I support the ui files locally what won’t work and are there work arounds for them?