I don't want to clutter my main system by installing many programs. Flatpak, Snap may be the solution. But I prefer to run the whole OS with its own init system (a VM-like approach), but with chroot-like performance.
With Docker this can also be achieved, just like LXC. Docker is used here instead, simply because it is like a mandatory program for me these days.
I don't want to display GUI applications on VNC, or X Server clients. Rather coexist with the host's tty.
In this case I use tty10 (Ctrl-Alt-F10).
Feel free to choose another number as long as it doesn't conflict with the host (most distros will use 1 - 6, and 7 for Display Manager).
MIT