X11 desktops on buster without systemd

[Dan Ritter <dsr@randomstring.org>]

Thanks largely to posts on the debian-init-diversity mailing list,
I have a VM running with buster and XFCE4 without systemd.

The process is not great, but it is doable:

I started with a fresh stretch VM (since I wanted to test upgrading
into buster.)

1. Change /etc/apt/sources.list entries to point to buster
2. apt update && apt dist-upgrade
3. shutdown -r now

The system is now buster and systemd.
You might want to dump a list of packages now:
    dpkg --get-selections > packagelist

4. apt install -d sysvinit-core elogind

5. shutdown -r now

reboot, but pause the bootloader to make your init=/bin/sh

6. apt install sysvinit-core elogind

Ideally, at this point nothing except systemd would be uninstalled. In
practice, currently, an awful lot of things that you might actually want
get uninstalled.

7. echo needs_root_rights=yes >> /etc/X11/Xwrapper.config

8. shutdown -r now

9. re-install packages that you wanted. Good thing you have that
list, right?

At some point in the future I will try this on a laptop, and if
successful, on my main desktop.

-dsr-