I agree!
When we click on “modify”: we expect to expand automatically the corresponding component in the navigator.
For the drag and drop into components: that’s great!
A nice addition would be to have an alert or a toast notification that said: “You should be in modify mode for this component to be able to add element to it” when we try to drag elements into it without being in modify mode. Otherwise, if we try to drop something in the component, it’s not working… but we don’t know why.