Hi @vandung93!
Thanks for the details provided, and I apologize for the confusion on this.
We have reported the issue to our development team but, unfortunately, we don’t have any ETA on when this will be resolved. If it helps to know, we support WordPress 5.2 and above which comes with jQuery 1.12.4 and jQuery Migrate 1.4.1 and due to the current release schedule that jQuery 4.0 has, it’s been given a lower priority by our development team and we may not have it fixed soon.
It’s completely safe and these are just warnings that do not negatively affect the plugin in any way but we are actively monitoring the release schedule for jQuery and will be sure to resolve this when that time comes.
We appreciate your report and if you have any questions, just let us know.
Hope this helps!