This topic dates from 2020.
I installed Manjaro twice from scratch, first time I selected wipe disk - btrfs - swapfile: no subvolume is created. Swapfile is on / (note this could break Timeshift, according to Manjaro wiki!).
Second time I selected “swap with hibernation”, again, no subvolume is created and there is no hibernation support. Worse, a swap partition is created, even though this is not recommended for SSDs and for BTRFS.
I know how to create a swapfile properly for BTRFS and to have it support hibernation (see this topic), but I am suprised Manjaro/Calamares does not take care of this by itself, especially after noticing this topic from last year?
It seems a lot of effort has been spend already.