String.prototype['format'] causes downstream conflicts in Stellar for Wordpress

[jonjonsiler]

Adding format method to the String.prototype causes downstream conflicts with plugins such as Gravity Forms implementation of String.prototype.format in the Stellar for Wordpress library.
/src/utils/index.ts

String.prototype['format'] = function() {
  var formatted = this;
  for( var arg in arguments ) {
    formatted = formatted.replace("{" + arg + "}", arguments[arg]);
  }
  return formatted;
};