}
Document toDocument = toPanel.getDocument();
Selection toSelection = toDocument.getSelection();
// Copy argument or equation accross (non-destructively).
Position to = getLastPosition();
Equation toEquation = toPanel.pointToEquation(to);
if (toEquation!=null) {
toSelection.setCurrent(toEquation.getRoot());
}
// Clone and add as a new equation below the selection.
Equation equationCopy = getSelection().getCurrent().getEquation().cloneEquation(); // Include the entire equation: root and label etc.?