Virtual Scroll plugin not working

[rahsan0786]

Hi. I have been trying to implement tom select's virtual scroll plugin functionality into my existing tomSelect code. The issue is when I search for the first time, the firstUrl is retrieved as mentioned in https://tom-select.js.org/plugins/virtual_scroll/. However when I scroll down the list, the nextUrl is not loaded, neither there is any api hit for retrieving data. Code wise I have verified everything and even setup the sample code provided into a local html and js and its not working there as well.
My sample code for the implementaion I have made is provided in the link below.
https://jsfiddle.net/ahsan0444/qc03w69o/3/
Is there anything I am missing which is not mentioned in the docs clearly. Would be a great help if anyone could resolve this issue