Spot the bug in customer deduplication

Node 24 intermediate 4 min 1 issue to find

Find why customers with the same ID remain duplicated.

JavaScript

function uniqueCustomers(customers) {
  return [...new Set(customers)];
}

const customers = [{ id: 'U-1' }, { id: 'U-1' }];
console.log(uniqueCustomers(customers).length);

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