In the current implementation, hierarchical filtering is internally integrated in RadTreeListView's data engine. Recently we had a report about degraded performance of processing the child nodes while filtering, so we are exploring the option of separating it from the logic that handles root level nodes. In this way we will be able to add an API member that switches it on and off. Here
is the public feedback item that was logged for the mentioned report. You can follow it to track when the new property gets publicly available.
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