Hi Tuyen,
Thanks for contacting us.
As you said, we are also unable to download the ej2.min.js file from CDN in IE11 browser. Currently we are validating and will update you the further details on 19th August, 2019.
But we can run the sample using the same CDN links without any errors. Please check with this stack blitz link.
Please let me know if any concerns.
Regards,
Gurunathan