Offline Mode: Don't inform contacts that we are online
Several users asked for the option not to let contacts know when they're online.
Some of those users wanted to be online without their contacts seeing them as online. It isn't possible to be online without connecting to contacts, and the "show what you know" principle says that if we know a contact is connected, we should show that information in the UI, so that feature request was rejected - see #72 (closed).
Other users wanted to be signed in without their contacts seeing them as online. We can achieve that by providing an offline mode where the user is signed in but all transports are disabled. As mentioned in the discussion on #72 (closed), being able to toggle transports (#185 (closed)) may not fully address the need for an offline mode, as users may not understand that disabling all transports means they're offline. Also, the user may want to enable offline mode when signing in.