Traceback (most recent call last):
  File "/home/voegtlin/electrum/gui/qt/main_window.py", line 77, in onPress
    self.func()
  File "/home/voegtlin/electrum/gui/qt/main_window.py", line 2887, in run_network_dialog
    NetworkDialog(self.wallet.network, self.config, self).do_exec()
  File "/home/voegtlin/electrum/gui/qt/network_dialog.py", line 240, in do_exec
    self.network.set_parameters(host, port, protocol, proxy, auto_connect)
  File "/home/voegtlin/electrum/lib/network.py", line 370, in set_parameters
    if self.config.get('server') != server_str or self.config.get('proxy') != proxy_str:
NameError: global name 'server_str' is not defined