Data Refresh Queue: Clear completed should disable control update during delete

I have a long list of finished operations in the Data Refresh window. When I click on the "Clear completed" button the list flickers wildly during the deletion of each single entry in the list. Steps to reproduce: - Refresh a partition of a table with a decent amount of attributes several times (3-4x). - Fully expand the tree of all refresh operations, so that the list contains >100 rows. - Click on the "Clear completed" button. The rows are deleted one at a time while it is jumping around and the scrollbar refreshes every time. Just disable the refresh of the control before the delete starts. Refresh the window only after all rows have been deleted. Probably the same has to be implemented for the "Clear queued" button. - More appealing UI handling. - Faster UI response.