The ability to "lock" and "unlock" a component or group of components. When locked, they can not be moved, edited, deleted, rotated, or otherwise modified. The option to Lock/Unlock should be an icon directly on the selection toolbar. When locked, all other icons or menu items that allow you to modify the locked thing should either be hidden or grayed out.

Copy/Pasting (or duplicating) a locked component should create a non-locked component, but leave the original locked.

Hot key: Ctrl + Shift + L