I installed Gnome tweak and without changing anything there, there are now borders on the laptop screen. The left panel that comes standard is inside this border and is no longer responding. The window super key is working. I can no longer switch between programs. Removing it does not help.
To try to reset the display I change the resolution. I also tried dconf reset -f /org/gnome/.
Ubuntu 18.1 on a Lenovo 14 flex.