The real purpose of Klipper is to quickly paste saved text items into destination apps, and Klipper is launched when a user tries to fill text fields, so after selecting an item and pressing enter (or left click mouse) the item is set to be current clipboard cache and the user should click again ctrl+v to paste it. Wouldn't be clever to have a default (can be disabled) ctrl+v action that can be triggered immediately after pressing enter (or left click mouse).