What do these object spreads produce when keys overlap?
const defaults = { theme: "light", fontSize: 14, animations: true };
const saved = { theme: "dark", fontSize: undefined };
console.log({ ...defaults, ...saved });
console.log({ ...saved, ...defaults });
console.log({ ...defaults, theme: "blue", ...saved });
The answer
Work out every line it logs, in order. Then check.
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