Last week, for the first time ever, I had a good reason for installing more than one Linux distribution on my laptop's hard drive. Thanks to the fact that I began having major problems with a newer version of Parrot OS, I moved to Kali Linux six or seven months ago. I had been using Parrot OS for about two years before that and really liking it until it began acting as badly as some of the other Linux distros. Last week, I was curious to learn if the problems had been solved.
I had always booted alternate Linux distributions from USB sticks, but I was fairly sure I needed to fully install Parrot OS on my hard drive to see the full picture. I did not, however, want to wipe out Kali, because it runs well, and I have installed various applications that I did not want to re-install if Parrot OS was still problematic. I also did not have an extra hard drive lying around at the time. That left dual booting Kali and Parrot OS. I found this to be harder than expected, but I did learn a few things in the process that some readers may find useful.
shrug wrote
you can install linux on a btrfs subvolume.
during the installation you have to manually mount it on /target and skip the partitioning process. after continuing you'll probably get an error message where you hit 2xback and suddenly it continues. i could expand on this. is there (still) demand ?