R7 introduced an irritating Designer bug when copying elements - try it for yourself.
Select more than one design element (form, view, anything) and right-click the mouse, preparatory to getting the “Copy/Paste” box. Designer only retains the last selected element!!
Keyboard action (Edit) still works. And the mouse will also work, as long as you move the pointer away from the vicinity of the last line you selected.
Hope someone’s watching.