Sometimes fails with "Invalid body" error
 Only recently-sent KakaoTalk messages can be deleted
 To make your KakaoTalk account leave a channel, send the
leave command in a Matrix portal room. Simply leaving a Matrix portal room will keep your KakaoTalk account in the channel.
 Kicks in KakaoTalk are equivalent to bans in Matrix
 Might not get synced on backfill or initial portal creation. Might get synced on live update to channel name/description