Traceback (most recent call last):
  File "electrum\gui\qt\send_tab.py", line 571, in do_pay_or_get_invoice
  File "electrum\gui\qt\send_tab.py", line 514, in read_invoice
  File "electrum\gui\qt\send_tab.py", line 635, in check_payto_line_and_show_errors
AttributeError: 'str' object has no attribute 'line_content'