Maybe the framework assumes that every Mac app has an Assets.car file included nowadays as Xcode builds such a file.
But Xojo apps don’t have it by default.
Xojo could certainly build one - at least on macOS
It might require installing Xcode to have the actool command line tool
And that would preclude anyone building macOS apps on other platforms as the CAR file format is not very well documented so creating one on Windows or Linux could be problematic
Thanks - since I’m seeing the error with all sorts of bundles (Apple’s own) this is probably a “wait and see” thing right now.
[I had been filtering the Console.app on the name of my app, so I hadn’t seen the errors for other apps].