Valid Anagram Challenge - Accounts for Whitespaces, special chars and letter casing

validAnagram.js

const validAnagram = (str1, str2) => {
  // convert to lowercase and remove spaces
  str1 = str1.replace(/\s+/g, "").toLowerCase();
  str2 = str2.replace(/\s+/g, "").toLowerCase();

  // Check for length once whitespace is removed
  if (str1.length !== str2.length) return false;

  // Only nums and lowercase letters allowed
  const regex = /^[\w.-]+$/;
  if (!regex.test(str1) || !regex.test(str2)) return false;

  let chars = {};

  for (let letter of str1) {
    // Add in each letter to the store of chars
    chars[letter] = (chars[letter] || 0) + 1;
  }

  for (let letter of str2) {
    if (!chars[letter]) return false;
    else chars[letter] -= 1;
  }

  return true;
};

console.log(validAnagram("texTtwi stti!2me", "tim2et!wisttext")); // false