code: def _send_string_selection(self, string: str):
          
          backup = self.clipboard.selection  # Keep a backup of current content, to restore the original afterwards.
          if backup is None:
              logger.warning("Tried to backup the X PRIMARY selection content, but got None instead of a string.")
          self.clipboard.selection = string
          self.__enqueue(self._paste_using_mouse_button_2)
          self.__enqueue(self._restore_clipboard_selection, backup)
docs: Use the mouse selection clipboard to send a string.