This resolves the error formerly manifested as:
Traceback (most recent call last):
File "/home/janus/Skrivebord/lightning-rfc/tools/electrum/packages/jsonrpclib/SimpleJSONRPCServer.py", line 376, in _dispatch
return func(*params)
File "/home/janus/Skrivebord/lightning-rfc/tools/electrum/electrum/daemon.py", line 292, in run_cmdline
result = func(*args, **kwargs)
File "/home/janus/Skrivebord/lightning-rfc/tools/electrum/electrum/commands.py", line 87, in func_wrapper
return func(*args, **kwargs)
File "/home/janus/Skrivebord/lightning-rfc/tools/electrum/electrum/commands.py", line 697, in lnpay
return f.result()
File "/usr/lib/python3.6/concurrent/futures/_base.py", line 432, in result
return self.__get_result()
File "/usr/lib/python3.6/concurrent/futures/_base.py", line 384, in __get_result
raise self._exception
File "/home/janus/Skrivebord/lightning-rfc/tools/electrum/electrum/lnbase.py", line 887, in pay
sig_64, htlc_sigs = chan.sign_next_commitment()
File "/home/janus/Skrivebord/lightning-rfc/tools/electrum/electrum/lnhtlc.py", line 281, in sign_next_commitment
htlc_tx = make_htlc_tx_with_open_channel(self, *args)
File "/home/janus/Skrivebord/lightning-rfc/tools/electrum/electrum/lnutil.py", line 262, in make_htlc_tx_with_open_channel
commit.txid(), commit.htlc_output_indices[original_htlc_output_index],
KeyError: 0
