when you set up an instance, all will be empty. the moment an user subscribe to a community for the first time, that community will start appearing on all, for everyone to see.
for this reason all is different for every instance.
the motivation for it is resources. if a new instance would receive updates from all the communities on all the instances, it would be very much like ddos. and a small instance will not be able to endure it.
not really add.
when you set up an instance, all will be empty. the moment an user subscribe to a community for the first time, that community will start appearing on all, for everyone to see.
for this reason all is different for every instance.
the motivation for it is resources. if a new instance would receive updates from all the communities on all the instances, it would be very much like ddos. and a small instance will not be able to endure it.