Traceback (most recent call last):
  File "electrum/gui/qt/my_treeview.py", line 475, in showEvent
  File "electrum/gui/qt/history_list.py", line 506, in update
  File "electrum/util.py", line 482, in do_profile
  File "electrum/gui/qt/history_list.py", line 287, in refresh
  File "electrum/util.py", line 482, in do_profile
  File "electrum/wallet.py", line 1330, in get_full_history
  File "electrum/wallet.py", line 1132, in get_onchain_history
  File "electrum/util.py", line 1182, in func_wrapper
  File "electrum/address_synchronizer.py", line 103, in func_wrapper
  File "electrum/address_synchronizer.py", line 527, in f
  File "electrum/address_synchronizer.py", line 564, in get_history
  File "electrum/util.py", line 1182, in func_wrapper
  File "electrum/address_synchronizer.py", line 103, in func_wrapper
  File "electrum/address_synchronizer.py", line 527, in f
  File "electrum/address_synchronizer.py", line 873, in get_balance
TypeError: sequence item 0: expected str instance, NoneType found