Not working in ie 11

Hi, I found this project very interesting and I start coding a simple example with Internet Explorer 11.
The array.from polyfill does not work if the object is a Set. I found problems with Symbol and Map too. A quick fix is to replace lib\array.from with something like

if (!Array.from) {
Array.from = function () {

// The length property of the from method is 1.
return function from(arrayLike /*, mapFn, thisArg */) {
let retArray = [];
arrayLike.forEach(function (v) { retArray.push(v) });
return retArray;
};
}();
}

and replace symbol.polyfill.js with
import 'core-js/es6/symbol';
import "core-js/fn/symbol/iterator.js";
import 'core-js/es6/map';

I imported symbol.polyfill.js into store.js and keys.js

Any chance to have a newer version of the package with this fix_
Thanks