Some Apple iPhone X units have a strange green line running down the edge of the display
So let's say that your brand new $1,000 iPhone X is suffering from this green line. What can you do? At least one person took his handset back to the Apple Store where it was replaced. That tells us a couple of things. One, this is not a problem that can be solved with a software update. Two, Apple is willing to make this right by replacing a unit that suffers from this issue.
At least 25 iPhone X owners have posted pictures across social media and on Apple's support pages, revealing this ailment. Right out of the box, these units appeared to be working perfectly, and reportedly none of the units were damaged. Instead, the green light appeared out of nowhere, running down either the left or right side of the phone. This seems to affect iPhone X models in various regions around the world, and in both the 64GB and 256GB variations. Turning the phone off and re-booting it doesn't get rid of the issue.
source: @mix0matosis via MacRumors