67P/hyperchannel

export default function urlBase64ToUint8Array(base64String) {

  let padding = '='.repeat((4 - base64String.length % 4) % 4);
  let base64 = (base64String + padding)
    .replace(/-/g, '+')
    .replace(/_/g, '/');

  let rawData = window.atob(base64);
  let outputArray = new Uint8Array(rawData.length);

  for (let i = 0; i < rawData.length; ++i) {
    outputArray[i] = rawData.charCodeAt(i);
  }

  return outputArray;

}