[messaging] "Appear offline" mode for Ricochet

[Sarah Jamie Lewis]

Hi George,

> In any case, I'm interested in more solutions to the presense problem
for Ricochet because it's really annoying me!

This is something I've been thinking about lately.

I believe the only way this could work given the Ricochet threat model is
to use multiple identities. Any other solution leaks information at the
network level or is purely cosmetic (which I think for other status like
away and busy works fine).

The UX/Protocol doesn't support this at all yet (unless you use multiple
clients), but theoretically, you could have a single introduction identity
which then (during the initial contact request) forwards to a different
identity. This could be done per contact group (e.g. I could have a
"friends" group or a "work" group and appear online or offline to each
group by disabling the respective hidden service.) or per contact user.

There are some drawbacks with this approach, mostly around managing the
additional hidden services - although these seem tractable.

I'm sure John has other thoughts on this.

Thanks,

Sarah