Followup to Santiago's report:
The script is also reporting that my Dell 3260CFF (Compact Form Factor)
is not on AC power when it is since it doesn't have a battery option.
The following may be of some help:
$ sh -x /sbin/on_ac_power
+ set -e
+ OFF_LINE_P=no
+ [ -d /sys/class/power_supply/ ]
+ test -d /sys/class/power_supply/hidpp_battery_0
+ test -r /sys/class/power_supply/hidpp_battery_0/type
+ cat /sys/class/power_supply/hidpp_battery_0/type
+ type=Battery
+ test -d /sys/class/power_supply/ucsi-source-psy-USBC000:001
+ test -r /sys/class/power_supply/ucsi-source-psy-USBC000:001/type
+ cat /sys/class/power_supply/ucsi-source-psy-USBC000:001/type
+ type=USB
+ [ -r /sys/class/power_supply/ucsi-source-psy-USBC000:001/online ]
+ cat /sys/class/power_supply/ucsi-source-psy-USBC000:001/online
+ online=0
+ [ 0 = 1 ]
+ [ 0 = 0 ]
+ OFF_LINE_P=yes
+ [ yes = yes ]
+ exit 1
$
The H/W doesn't actually have a battery option but does use a laptop
style power brick or USB-C to supply power.
