js找出两个数组中不同的元素

arr1 = [1, 2, 4, 556, 77, 89, 9];
arr2 = [12, 12, 3, 4, 5, 6, 7, 87];
let difference = arr1
    .filter(x => arr2.indexOf(x) == -1)
    .concat(arr2.filter(x => arr1.indexOf(x) == -1));
    console.log(difference)