[x1798DE]

> Multiple identities seems like a problem best solved by client-side tools (e.g. tweetdeck handles this usage really well IME).

I agree in the sense that I might want something like a role / brand identity and a personal identity, but I was considering something more like instance-specific aliases or identities. The first-pass solution at this would be one where you can specify that different accounts on different instances are all the same person so that posts duplicated on multiple instances (i.e. in the local feed of that instance) can be de-duplicated in a federated feed that includes more than one of the aliases.

External clients won't be able to stop people from following one of the alias instances and not the "canonical" instance, and they won't be able to make servers de-duplicate content that is cross-posted to multiple instances. If this isn't addressed in the protocol, you'll get people hacking together "boost bots" that duplicate your identity to multiple instances (with the issues that comes from hacking something like that into your client) in the same way that they are already using "follow bots" that just randomly follow tons of users on other instances to force more thorough federation between instances.