I get an "Unknown Error" message when the packager (1.2.9) is creating the xar archive. This used to work a couple years back. I updated to the latest packager version (1.2.10) and it still gives the error. Also, I get this error both in the GUI and when running the packagesbuild command.
The OS is Catalina (10.15.7) and the payload is around 2.2 GB I would guess. BTW, I have plenty of disk space.
Any thoughts?