The LG V series has a history of including secondary displays, which are often built into their large phablet-scale screens. If a new leak is to be believed, this feature has returned to the V50 ThinQ - sort of. It consists of images showing a case that gives the upcoming LG flagship an entire extra screen.
https://www.notebookcheck.net/Possible-LG-V50-pictured-with-second-screen-case-in-new-leaks.410695.0.html