These correspond to the “special” app-specific folders that you see in Finder’s view of iCloud Drive.

Apple first-party apps with specific iCloud support, prefixed with com~apple~.Developer ID or “App ID Prefix” (I think?) followed by bundle identifier.After some digging around, I could not discern a difference between them. There appear to be three general types of directories present. If you cd there and ls, you will see its entire contents, most of which is not viewable via Finder. Its actual location on disk is at ~/Library/Mobile Documents/. iCloud Drive displays as a special directory in the sidebar of Finder. The iCloud Drive folder on your Mac is tricky. I’ve had good luck with iCloud Drive for the past few years, but I am terrified and paranoid of getting caught in the middle of an iCloud clusterfuck, so I backup what I have in iCloud periodically using rsync. I still use it, despite a few bad experiences in the past, because the best alternatives are questionable for other reasons. Yet a lot people still use it, often without any problems. Unfortunately, iCloud does not have a good reputation for being reliable, especially during beta releases of iOS and macOS.

Backup mac to icloud drive