File "/usr/lib/python3/dist-packages/electrum/gui/qt/network_dialog.py", line 73, in on_update
    self.nlayout.update()
  File "/usr/lib/python3/dist-packages/electrum/gui/qt/network_dialog.py", line 342, in update
    name = chain.get_name()
  File "/usr/lib/python3/dist-packages/electrum/blockchain.py", line 250, in get_name
    return self.get_hash(self.get_max_forkpoint()).lstrip('0')[0:10]
  File "/usr/lib/python3/dist-packages/electrum/blockchain.py", line 519, in get_hash
    raise MissingHeader(height)