Comment 6 for bug 1060893

It is not possible to install more than 1 fully working btrfs installation. It's not possible to have more that one 1 @. In total, across all devices attached to the system. This is expected and warned about. More than 1 simultaneous btrfs installation is not supported. If you have enough knowledge to modify grub / initramfs-tools / debian-installer to support this case, such work will be appreciated upstream in Debian and hence in Ubuntu as well.