See the attached GIF. I used video slow motion on my LG G7 to take this of my HP EliteBook at 100% brightness.

It causes dizziness/vertigo/strain on the EliteBook's internal laptop display, but is fine on external monitors.

Is this PWM? Or LCD inversion?

See below GIF, the "shimmering" in MS Notepad:

Looks like a moiré effect caused solely by the camera.

dev