They will need to do some work to make that safe. There has been a number of famous attacks able to determine some people's browsing history entirely on the cli

They will need to do some work to make that safe. There has been a number of famous attacks able to determine some people's browsing history entirely on the client side. I think most of them have mitigations in place, but we can't dismiss the fact browser itself still contains history. Anyway, what kind of content delivery are you thinking about?