Surface Pro 4, i7 6650U, Win 10 with latest updates.
Yep, same problem, ongoing now for a few months. I put it down to overheating at first, as I was running some heavy apps (large file GIS processing). The back of the case felt very hot to touch for more than 10 secs or so. The screen also feels hot to touch. I
installed "Core Temp' to see if the CPU was overheating... not really it was getting to ~70 max, with theoretical limit of 100.
I did everything suggested in the thread above, re updates, software fixes, etc. I also turned off Cortana and some other apps running in background to reduce CPU load. I had a technician clean the interior by blowing canned compressed air through the rear
vents, which helped temporarily. No way to see how effective that was, I can't split the case. However its still ghosting even on low CPU temps of mid 40s. I'm running a battery fan aimed at rear case which makes a big difference to core temp, but even so
the only way I can use this machine after 30 minutes now is to have an external monitor.
The ghosting happens whether or not I'm running the aux monitor, and happens whether on battery or on mains power. As described by another poster above, I get a greyed line about 3-4mm thick across top of screen, and lately also a black shadowed area starting
in from top right (BTW no diff in temp there to touch). If I take a screen grab, the shadows are not visible, but below is a pic from phone.

I wonder if this can be ruled out as software issue which overloads the hardware... it seems to have appeared quite soon and suddenly after an MS update about October 2017.
I'm out of warranty by a good six months, but its clear I'm not an isolated case, its a systemic problem and/or defective product. There's no MS shop in the whole of SE Asia where I'm travelling, and there's only one in the whole of Australia which is a
long way from where I live.... total crap for service !! MS, if you want to ever want this poor fool to buy another MS hardware product, you'll have to start replacing SP4s for everyone with this problem, AND get a better service network.