Unfortunately several #Ghostbsd #MATE configuration windows are taller than my laptop's 768 pixels. I made both the top and bottom panels autohide, but a better solution is to use xrandr
sudo pkg install xrandr
type xrandr to get the name of your display, in my case LVDS-1 on my Thinkpad X220.

To change 16:9 screen resolution, you can type:
xrandr --output LVDS-1 --panning 1600x900 --scale 1.171x1.172
or
xrandr --output LVDS-1 --panning 1920x1080 --scale 1.406x1.406
To get back to the original resolution type:
xrandr --output LVDS-1 --panning 1366x768 --scale 1x1
You can add this to a keyboard shortcut and use it when those annoying panels show up the next time.