Release notes:

• Convert array iterator for loops to index iteration.
  • This avoids conflicts with additional methods defined on the Array prototype. It is generally not good practice to modify global prototypes with new methods (and if you do, you should make sure they are not enumerable: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/defineProperty#enumerable), but this should reduce the chance of conflict when you are using clipboard-polyfill.