Now that Chrome OS 80 is out, any new Linux Crostini containers will run Debian Buster instead of Stretch. I restored a Stretch container backup on Buster but it didn’t work.
Debian Buster arrived in July but the Crostini container for Linux on Chromebooks wasn’t ready for it. Now, after months of work, it looks like Chrome OS 80 is the planned implementation.
Debian 10 Buster lands this week but Linux on your Chromebook will still run Debian 9 Stretch for some time. If you want to upgrade your Project Crostini container to Buster in advance, here’s how.