I'm just using Arch in my toolbox. Can't run into upgrade troubles if you run a rolling release system
So this isn't really an answer on how to migrate but this solution has worked well for me.
I define the toolboxes config with it, and if it gets destroyed, recreating it is as simple as creating a new one with the same name. You could upgrade or downgrade by just creating a new toolbox with the version you want.
From Wikipedia, the free encyclopedia
Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).
Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
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