Outside of ancillary literature, none of the sequel trilogy movies provided an explanation why C-3PO had a red arm coming into Star Wars: The Force Awakens. I’m inclined to think there’s a much simpler explanation, one involving R2-D2, and a good serving of red paint.

S.H.Figuarts / C-3PO (Star Wars: The Force Awakens)
S.H.Figuarts / R2-D2 (Star Wars: A New Hope)
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