I thought that's what Electrolysis was. We've switched to an ESR release with e10s disabled because of an incompatible add-on listed as compatible. Annoying, because the idea is if an add-on doesn't work with e10s, e10s will be automatically disabled. And of course in this case it doesn't since the add-on works "great" with it!

I believe the main thing Electrolysis does is split the UI and rendering into separate processes. It also creates separate processes for some other tasks. But as far as I know it doesn't give each tab a separate process.