Thats obviously because you skinned Skada with AddOnSkins, disable the Skinning in the AddOnSkins Options for Skada and you can Customize you Skada like you want, in this case ScrubKitty uses Details Damage Meter, which is in my opinion alot better than Skada/Recount et cetera.
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Well i had to Build my UI from the Dust up, since i had some weird Issues with my Importet one.
Im not going to Upload my whole UI, instead ill give you the Modified LUA texts from me and kheath, just Replace all of the Text in the Files with the ones from the Pastebin.
API - Goes into AddonSkins - Core "API.lua"
https://pastebin.com/jJkxH89g
toolkit - Goes into ElvUI - core "toolkit.lua"
https://pastebin.com/2wfSrvEH
untiframes - Goes into ElvUI - Modules - unitframes "unitframes.lua"
https://pastebin.com/tBeXDHiG