The Forma uses a flexible plastic TFT, it wouldn't showcase the usual glass cracks shown on earlier... glass TFT when they... crack

.
That, on the other hand, could be a badly seated flex cable. Or something worse. So, yeah, if it's under warranty, call CS.
And, no, this has nothing to do with the Forma's famous frontlight sidebar of doom (because, first: duh. And, second, the frontlight is off on the "connected to a computer" screen).