The operator run when dropping objects would duplicate the dropped object and place that in the scene, even though that was just appended. Addressed by making the duplication optional for the operator. If the duplication is not requested, the object is just added to the scene (if needed), repositioned based on the drop location and selected (deselecting other objects). This makes the operator work as expected when using it to drop assets. Reviewed as part of https://developer.blender.org/D11536. Reviewed by: Bastien Montagne