The foundational work is there, it's currently still going through testing, although you can already manually enable it and it works rather well, but as of righ

The foundational work is there, it's currently still going through testing, although you can already manually enable it and it works rather well, but as of right now it's not planned to have complete separation for each individual tab, as that just chews up a lot of resources with relatively little gain in performance. What's planned instead, is to use a set number of processes across all tabs. So, if this would be two processes, then every other tab will share a process with one another. And they'll probably have around 5 processes for tabs at a maximum once this is fully rolled out, at least for the foreseeable future. You can manually change this maximum number of processes in about:config, though. And if you do set it to something like 500, i.e. just a very big number that you're not likely to hit in number of tabs, then it will separate each tab into its own process, with whatever performance problems come with that.