>as soon as a sub in that chain is offline, the link breaks. anyone can seed comment.author.previousCid, so the author can seed his own profile cids, or people who recently downloaded that specific cid would also seed it. since most people are just using the web version at the moment, then if the sub is down, the cid would probably also be down, but in the future it will be less of an issue. also in the future the user will probably include more links in each comment so that it's more reliable. also in the future the users will probably have an option to publish IPNS records using their plebbit public key, so a cid will not be needed to view a user's profile, and also they'll be able to reorganize the linked list differently, maybe using pages similar to subplebbits. once P2P in the browser is done implementing and public RPCs are implemented, this will even be possible by web peers. A user can seed his IPNS record in the browser while he's online, and when he's not online, his IPNS record can be cached by gateways and/or seeded by public RPCs.