The TreeList footer differs from the one in Grid. In TreeList we have a column footerTemplate - it is not a separate div out of the scrollable content, but it is a table row inside the scrollable content. And different levels may have their own footerTemplate row as you could see in the Aggregates demo
. So its purpose is different than the Grid footer.
As a workaround, if your page is not scrollable you may set fixed position to your footerTemplate and adjust it right below the TreeList through the top property. You may need to adjust the columns width as well. Another approach could be to display the respective data from the footerTemplate in a div below the TreeList.
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