Comment 5 for bug 2033308

I have been able to reproduce this issue and create a patch to fix the problem of packaged preferences.d files being removed. I have tested this successfully with mantic base images with ubuntu-advantage-tools 29.3

From changelog history, it has been hard to understand the history of lb_chroot_archives or the intention of the preferences.d files removal. As such, the patch takes the safest approach of not altering the behaviour of removing the packaged preferences.d files, but instead ensures that the packaged preferences.d files are backed up and restored as part of lb-chroot_archives install and remove stages.