Looks like lightdm IS dm-tool. There's not much else. 

~$ apt-file find dm-tool
lightdm: /usr/bin/dm-tool                 
lightdm: /usr/share/bash-completion/completions/dm-tool
lightdm: /usr/share/man/man1/dm-tool.1.gz

lightdm will also pull in lightdm-gtk-greeter

I think you may be right that it changes desktops.  I'm a little hazy lately and should stop trying to answer questions as I'm batting zero today.

Thanks for your attention, anyway. I hope the "Get Well Soon" option is selectable for you.

On the slim panel there is a note to  Press F1 to select sessions. Did that not work?

When I press F1 at the slim panel, the words "Session: Xfce Session" appears on the slim panel. This does not seem to do anything in my case. I have the idea from several years ago that this was meant to switch between different desktops, if one had them installed (Xfce, ICEWM, etc), but the memory is hazy.

Furthermore, I have the idea that I would only see the slim panel if I was logged out? I know I can switch users by logging out, and then logging back in as the other user, but I would prefer to avoid logging the original user out (in case it is doing something that I would prefer to not interrupt)

I imagine it's one of those features which are 'bloat' to some, and very useful to others.

Regarding the result from the search, in what way is it misleading? It *seems* to be telling me that, if I want dm-tools, I need to install lightdm. So, it appears to agree with your suggestion.

I would suggest you remove slim (isn't really maintained any more) and install lighdm. Then you will have the full set of features for multiusers.

rolfie

Chimaera (64-bit,runit) seems to be working out quite nicely, despite beta status, but there are one or 2 niggles - perhaps I am missing something?

I notice the Switch Users option seems to be greyed out (or grayed out) in the Action Buttons area of my panel. I read somewhere on the Internet (so it must be true) that SLiM does not actually offer User Switching.  I would really like to be able to easily switch between graphical desktops as my partner and I use the same PC with different usernames.  What options are there?

It seems I can use CTRL+ALT+Fx to get to another tty, logon there as a different user, and invoke "startx". This brings up the desktop of the newly-logged-in user. It feels a bit hacky, but that's not too abysmal. Are there any possible pitfalls to using this method in day-to-day sharing-is-caring computer operations?

In a previous life with another distro, and presumably another display manager, I was able to access both a "Switch Users" button, and also to use the "Action Buttons" / "Lock Screen" function which gave me a "New Login" button. This would then allow the other user to enter their credentials. However, in my current dispensation, this gives me the disappointing message

xscreensaver: <time> could not execute "dm-tool": no such file or directory

I assume this below is apt telling me that dm-tool is part of lightdm? (If so, that's a nice feature of apt.)

apt search dm-tool
Sorting... Done
Full Text Search... Done
lightdm/testing 1.26.0-7+devuan3 amd64
  simple display manager

Is there an equivalent available for SLiM?