JSFiddle - React, Tailwind, and code Playground

JavaScript

Array.prototype.equals = function(arr) {
  if(this.length !== arr.length) return false;
  
  for(let i in arr) {
    let t = this[i],
        a = arr[i];
    
    if(t instanceof Array && a instanceof Array) {
      if(!t.equals(a)) return false;
    } else if(this[i] !== arr[i]) return false;
  }
  
  return true;
}

console.log([1, 2, [3, 4], 5, [6, [7, 8, [91]]]].equals([1, 2, [3, 4], 5, [6, [7, 8, [91]]]]));
console.log([1, 2, [3], 5, [6, [7, 8, [91]]]].equals([1, 2, [3, 4], 5, [6, [7, 8, [91]]]]));