As described in the Feedback portal thread, linked in my previous response, due to the asynchronous loading mechanism of each nested level of data and the fact that the TreeView does not have a scrollable container by design, introducing a virtual scrolling functionality is not feasible. That is why we will introduce a "Load more" mechanics for addressing scenarios in which the TreeView contains too many items.
This functionality is in its final stages of development and testing, and should be available for our next official release, planned for mid-May.
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