This question seems so obvious I can't be the first to ask it, but searching this list didn't turn up anything.
How do I add an existing class to my class diagram? I have multiple class diagrams, one of which already contains a certain class. I'd like to add the same class to another diagram.
I've tried dragging the connection arrow from a class already in the diagram, choosing "Usage To", then choosing "Existing Element", but nothing happens. I've also tried opening up the .uml model and dragging the class I want over to the diagram, but nothing there either. I've also tried adding a shortcut from the diagram right-click menu, but this doesn't seem to be same thing (for example, it has a shortcut arrow).