There are two options when copying or moving a button. We can create a copy of the button on the same page or move the current button to a another page.

Select the Move/Copy Button Option. The dialog below will appear.

The button on the left "Page 1" set the page to copy the button to. If it is the current page there will be a copy of that button made to the current page appending the word 'copy' to the end of the button. Once the page is selected, press the Copy/Move Button. This create the copy either on the current page or desired page and ask whether to delete the Original button.