A number of iPhone 11 users had a problem with a strange green appearing on their device screens for a few seconds after unlocking, and the reason for this phenomenon is not clear.
The most affected devices are: iPhone 11, 11 Pro, and 11 Pro Max, and some iPhone X and XS users also faced the same problem according to user complaints online.
Many users said that the green color only appears when the devices "Dark and Night Shift" are on or if they are in a dark room.
Users have also reported a problem after the iOS 13.4 update, although some have experienced a problem after upgrading to iOS 13.5, according to the Engadget technical website.
A user said that the green color disappeared when installing the iOS 13.5.5 beta update, so it seems likely that it's a problem with the software and updates, although the cause so far is still unknown.
Many users said that the green color only appears when the devices "Dark and Night Shift" are on or if they are in a dark room.
Users have also reported a problem after the iOS 13.4 update, although some have experienced a problem after upgrading to iOS 13.5, according to the Engadget technical website.
A user said that the green color disappeared when installing the iOS 13.5.5 beta update, so it seems likely that it's a problem with the software and updates, although the cause so far is still unknown.
source; here