I've had an experience after this last round of upgrades his week.
My "user" lost all root access privileges. So, I couldn't launch Synaptic, gparted, and grub customizer.
So I learned how to give user sudoers temp root by edit of visudo (I hate nano btw and so exported to Leafpad
Then I learned to edit /etc/passwd to give user root level powers by editing to change UID and GID to 0. (Yes. I made an additional backup)
So, I learned a lot, but still can't get "user" to show up in LightDM menu AND in terminal can't get down to a regular $ state. Any ideas?