> I thought Chrome was famous for being a resource hog.

That's only in comparison to Safari and Edge. If you open enough tabs to cause memory issues on Chrome, Firefox would have frozen and slowed down to a crawl before filling the memory, anyhow, and electrolysis still isn't in a state where it could change that: there's still one process for the renderer so if enough intensive webpages are run your web browsing experience will still slow down.