I have ubuntu 16.04 running on BTRFS, but since some pages said that GRUB2 (2.02-beta2) cannot boot from BTRFS, I made a boot partition in ext4 for /boot. But this partition is too small now, only 150MB. Can I put /boot onto BTRFS? And how can I test it without making my system unbootable?
Is it possible to create a /boot2 directory in btrfs, copy the files from /boot into it and change /boot/grub/grub.cfg by adding a new menu entry saying "boot from /boot2"?
(I have not activated UEFI)