I created an Ubuntu-core Raspberry Pi 3 B+ image using the example shown on https://docs.ubuntu.com/core/en/guides/build-device/image-building
It was straight forward and easy to implement. Apparently the file system is read-only.
sudo usermod -aG docker $USER
usermod: /etc/group.1763: Read-only file system
usermod: cannot lock /etc/group; try again later.
Did I mess up or is that normal?
Can I have my file system read-write?