There's an add on that lets you create custom containers, a container acts as it's own session in a way, content, cache, cookies etc are all localised to one container
For example, you open youtube in one then open gmail in another container, neither one will know you're logged into the other
Moderation is not the issue, the sheer cost to host the tremendous amount of data is very likely to be a reason an instance goes down, thats what I'm getting at