here's a save, whiterun facing some houses, load it up and the bug will be present on the roofs (like in the video) this is vanilla ultra settings, so fFirstSlice 2000, fShadowDistance 10000 and 4096 shadow resolution no mods if you test the save, please report your video card model. I suspect this is a shader issue tied with specific hardware I have a gtx960 btw https://www.dropbox.com/s/6r63si2fe4u58by/Save3_00000000_0_4E6F7264_WhiterunWorld_000036_20190701212713_1_1.ess?dl=0