1
let a = [1, 2, 2, 1];let b = [2];let aSet = new Set(a);let bSet = new Set(b);let intersection = Array.from(new Set(a.filter(v => bSet.has(v))))console.log(intersection); // [2]

1
let a = [1, 2, 2, 1];let b = [2];let aSet = new Set(a);let bSet = new Set(b);let intersection = Array.from(new Set(a.filter(v => bSet.has(v))))console.log(intersection); // [2]