Fix crash on attempting to send to an unjoined channel

http2irc.py

@@ -445,11 +445,19 @@ class IRCClientProtocol(asyncio.Protocol):
 			command, channels, message = data.decode('utf-8').split(' ', 2)
 			for channel in channels.split(','):
 				assert channel.startswith('#') or channel.startswith('&'), f'invalid channel: {channel!r}'
+				try:
+					modes = self.get_mode_chars(self.server.channels[self.server.casefold(channel)].users.get(self.server.casefold(self.server.nickname)))
+				except KeyError:
+					# E.g. when kicked from a channel in the config
+					# If the target channel isn't in self.server.channels, this *should* mean that the bot is not in the channel.
+					# Therefore, don't send this to the broadcaster either.
+					# TODO: Use echo-message instead and forward that to the broadcaster instead of emulating it here. Requires support from the network though...
+					continue
 				user = {
 					'nick': self.server.nickname,
 					'hostmask': f'{self.server.nickname}!{self.server.username}@{self.server.hostname}',
 					'account': self.server.account,
-					'modes': self.get_mode_chars(self.server.channels[self.server.casefold(channel)].users.get(self.server.casefold(self.server.nickname))),
+					'modes': modes,
 				       }
 				self.irc2httpBroadcaster.send(channel, {'time': time_, 'command': command, 'channel': channel, 'user': user, 'message': message})
 		return time_