3 way with MCA, Regen and FirstPerson model. causes the players head to be rendered in first person. MCA already addressed an identical issue between first person mod and itself but it seems regen is changing things so something in their fix isn't working as intended. most likely this needs to be fixed on MCA's side but im putting this here to document it and link the respective issue reports together.

tr7zw/FirstPersonModel#322
Luke100000/minecraft-comes-alive#469

https://youtu.be/Ocscc3GbUUU

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