IE11 Scroll is not moving when we click on down arrow of the scroll bar in scrollable results section

[khari512]

When we click on the scroll bar down arrow in auto complete results, the scroll is not moving down in IE11. Its working fine in chrome.
I am able to see this issue in Jquery auto complete demo site itself.
https://jqueryui.com/autocomplete/#maxheight

Steps to reproduce:

1. Open the above link IE11.
2. Type "a" in input box.
3. click on the down arrow of the scroll bar continuously.