system
A chat on subreddit /r/pcmasterrace
human
Chrome was definitely faster than FF when it first released. FF completely rewrote their engine to compete. Per tab application threads for instance weren't a thing back then. An unfortunate side effect was that addons for FF are significantly less capable than they used to be.
gpt
Even now, I get substantially better video playback performance on my underpowered laptop in Chrome if I'm running an external monitor. That said, I just use Firefox for everything else.