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                <textarea id="target">Secret Text, now Fingerprinted</textarea>




                function zeroPad(num) {
  return '00000000'.slice(String(num).length) + num;
function textToBinary(username) {
  let answer = username.split('').map(char =>
    zeroPad(char.charCodeAt(0).toString(2))).join(' ');
  return answer;
function binaryToZeroWidth(binary) {
  return binary.split('').map((binaryNum) => {
    const num = parseInt(binaryNum, 10);
    if (num === 1) {
      return '​'; // zero-width space
    } else if (num === 0) {
      return '‌'; // zero-width non-joiner
    return '‍'; // zero-width joiner
  }).join('') // zero-width no-break space

const binaryName = textToBinary('barzik');
const zeroWidthString = binaryToZeroWidth(binaryName);
console.log(binaryName); // "01100010 01100001 01110010 01111010 01101001 01101011"
document.getElementById('target').value += zeroWidthString;