==  added functionality ==

I remembered from previous times I've used i3 that there'a a
"back-and-forth" function, where you can switch back&forth  between
desktops by repeating the same $mod+n keys

I added 

workspace_auto_back_and_forth yes


While checking on the web for the exact format for the setting I
stumbled on a page [0] with some other i3 tweaks - of particular
interest the ability to more easily 

1) lock
2) logout
3) suspend
4) hibernate
5) reboot
6) shutdown


This laptop has no systemd, so I modified the actions to call shell
scripts where I put the "sudo" commands for

pm-suspend-hybrid
pm-hibernate
shutdown -r now
shutdown -h now


I had to install the "pm-utils" package and edit
'/etc/elogind/logind.conf' to enable "suspend" and "hibrenate"

[Sleep]
AllowSuspend=yes
AllowHibernation=yes

and 'service elogind reload"


The i3 config stanza is now:



# shutdown / restart / suspend...
set $mode_system System (l) lock, (e) logout, (s) suspend, (h) hibernate, (r) reboot, (CTRL+s) shutdown

mode "$mode_system" {
    bindsym l exec --no-startup-id i3lock, mode "default"
    bindsym e exec --no-startup-id i3-msg exit, mode "default"
    bindsym s exec --no-startup-id i3lock && ~/bin/suspendi3.sh, mode "default"
    bindsym h exec --no-startup-id i3lock && ~/hibernatei3.sh, mode "default"
    bindsym r exec --no-startup-id  ~/bin/rebooti3.sh, mode "default"
    bindsym Ctrl+s exec --no-startup-id ~/bin/shutdowni3.sh, mode "default"

    # back to normal: Enter or Escape
    bindsym Return mode "default"
    bindsym Escape mode "default"
}

bindsym $mod+BackSpace mode "$mode_system"


pressing $mod+backspace puts the menu onto the status bar with
options

l = lock
e = quit i3 
s = suspend (hybrid)
h = hibernate
r = reboot
Ctrl+s = shutdown

Easier the either opening a new terminal and entering the commands
or using i3's normal exit $mod+shift+e and needing to use the mouse
to click the "Yes" button to dump you back in the console...


[0] https://thevaluable.dev/i3-config-mouseless/