First, activate "Enable Drag & Drop" in the work window.
Supports can be moved when holding down the left mouse button. If you also press the CTRL key, the marked elements are copied.
Generally, the "Move/Copy" function is not available for these elements in the shortcut menu.
If you want to copy nodes, lines, or surfaces, including supports, you have to select both the objects and the supports. By right-clicking the object (not the support), you can also use the "Move/Copy" function.
In the same way, in RFEM you can quickly assign FE mesh refinements to objects as well as move or copy them.