I was trying to use guestfish to increase a qcow2 partition without booting live and fdisking and all that mess. So I tried to run it and was getting

# virt-filesystems --long --parts --blkdevs -h -a disk.qcow2
libguestfs: error: /usr/bin/supermin-helper exited with error status 1.
To see full error messages you may need to enable debugging.
See http://libguestfs.org/guestfs-faq.1.html#debugging-libguestfs

Scratching my head a bit and figured out you need to update the guestfs appliance packages

update-guestfs-appliance

Now the command works!

# virt-filesystems --long --parts --blkdevs -h -a disk.qcow2
Name       Type       MBR  Size  Parent
/dev/sda1  partition  83   3.8G  /dev/sda
/dev/sda2  partition  82   976M  /dev/sda
/dev/sda   device     -    5.0G  -

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