The described behavior was introduced in Q1 2015 due the virtualization functionality. It wasn't compatible with the dynamic rendering of the UI. The new behavior allows to select/unselect items using keyboard navigation, which before was not possible. Also many users wanted from us to enable this selection behavior due the need to display "checkbox" elements (to keep the selected items visible).
This breaking change is documented in our "Changes and backward compatibility"
For now, I would not be able to provide any feasible workaround for this change.
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