Screen blank in the morning

[dogshed]

Screen is blank in the morning. I posted this before in the post-installation category and people suggested it was the USB drive.
It's happened a couple of times since without anything other than the power cord plugged into the computer.
It's a Dell XPS 12 from 2014.
I think it may be turning off my screen blacklight and failing to turn it back on.
Here are a couple of messages that are repeated in my syslog:


Aug 20 23:00:46 dog org.kde.KScreen[3095]: kscreen.xcb.helper: RRNotify_OutputProperty (ignored)
Aug 20 23:00:46 dog org.kde.KScreen[3095]: kscreen.xcb.helper: #011Output: 67
Aug 20 23:00:46 dog org.kde.KScreen[3095]: kscreen.xcb.helper: #011Property: Backlight
Aug 20 23:00:46 dog org.kde.KScreen[3095]: kscreen.xcb.helper: #011State (newValue, Deleted): 0
Aug 20 23:00:47 dog org.kde.KScreen[3095]: kscreen.xcb.helper: RRNotify_OutputProperty (ignored)

I also have this in syslog:

Aug 21 06:18:48 dog org.kde.KScreen[2939]: kscreen: Primary output changed from KScreen::Output(Id: 67 , Name: "eDP1" ) (
"eDP1" ) to KScreen::Output(Id: 67 , Name: "eDP1" ) ( "eDP1" )
Aug 21 06:19:43 dog org.kde.KScreen[2939]: message repeated 15 times: [ kscreen: Primary output changed from KScreen::Outp
ut(Id: 67 , Name: "eDP1" ) ( "eDP1" ) to KScreen::Output(Id: 67 , Name: "eDP1" ) ( "eDP1" )]