When I try as nc50lc suggested, removing "https://" from the address, I get the following error message in the client:
E | lnworker.LNWallet.[LN] | Exception in sync_with_remote_watchtower: TypeError("'NoneType' object is not subscriptable")
Traceback (most recent call last):
File "/home/aaaa/.local/lib/python3.8/site-packages/electrum/util.py", line 1118, in wrapper
return await func(*args, **kwargs)
File "/home/aaaa/.local/lib/python3.8/site-packages/electrum/lnworker.py", line 697, in sync_with_remote_watchtower
if not (parsed_url.scheme == 'https' or is_private_netaddress(parsed_url.hostname)):
File "/home/aaaa/.local/lib/python3.8/site-packages/electrum/util.py", line 1371, in is_private_netaddress
if host[0] == '[' and host[-1] == ']': # IPv6
TypeError: 'NoneType' object is not subscriptable