Oh, one problem with your approach though. It means that we'll be stuck with .tar.xz for pre-Xenial, whereas with my suggested solution, recent LXD would be able to use squashfs on any release publishing the .squashfs and older LXD that doesn't know about squashfs would still work fine.
Oh, one problem with your approach though. It means that we'll be stuck with .tar.xz for pre-Xenial, whereas with my suggested solution, recent LXD would be able to use squashfs on any release publishing the .squashfs and older LXD that doesn't know about squashfs would still work fine.