My apologies, there was a mixup in the cases that led me to believe that this issue was fixed. Here is the information I received from one of the developers:
In v3.6, range selection for virtualized sources was added to the grid. In order to not kill performance, some breaking changes were required including the one you are noticing on the SelectedItems collection; however, the SelectionChanged and SelectionChanging events, which contain all the required information, were added to the grid.
Senior Technical Writer
- Xceed Software
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