Now I've been having this problem since I resubbed and it's really bugging me when I tank, or even play in general.
I've sifted through all my addons, disabling them to check which ones had and effect on the Name Plates and it turns out it's just Tidy Plates: Threat Plates.
Does anybody else have this issue?
Also is it worth using one of the other plate designs in Tidy Plates in the mean time or use Elvui's Name Plates as I don't know what either of those are properly like when tracking Threat?