So I’m getting weird adaptive tessellation cracks in 4.8 P4 (near the edges of the screen) as I move the camera around. It’s noticeable with an ocean shader with vertex displacement.
Tested Flat and PN Triangles tessellation with crack free displacement checked on and off… pretty much same result.
The same material setup worked fine in 4.7.
What changed exactly? 
right now the only way to fix it is to turn adaptive tessellation off but that kills performance of course.
The problem can also be seen in wireframe.
As you can see, the mesh at the top part of the screen is for some reason with no tessellation (that’s where you would see the crack in Lit mode).
This can only be seen at certain camera angles (and you need to have animated vertex displacement) so I understand if it’s difficult to catch but this have to be fixed :p.