Mood
3
Thank you for the tip, it did make the game look better! 
That said, it didn’t solve my issue. But… I also found out that my issue only happens when I play the Savage Wilds map, it does not appear in the Exiled Lands or on Siptah… And it only happens when I run, not when I stand still.
So I guess it’s somekind of mod issue, related to the map.