In the example of the screencast I am using local data virtualization
as I do not have access to the remote service serving the data, in this scenario the scrollbar is not resized, because the widget know the total of the elements and can correctly size before loading them.
It looks like all data is shown, but this is not the case, as you can inspect the view size of the dataSource as shown here:
As you can see from the video, the virtual view size is set to 100, while the total number of items loaded in the DOM is 51, and these elements will change when the user scrolls down.
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