Comment 7 for bug 1881932

I can just use windows. But this is not my option. Thanks. A full-fledged installer should support this simple things. Moreover a Debian installer had this support.

BTW Debian installer has not support installation on RAID1/0. And you can just first make an installation on usual partition and then add another one partition to the first one with 'btrfs device add' command and then perform a balancing with 'btrfs filesystem balance start -dconvert=raid1 -mconvert=raid1 /'.