I've given it a try, but macOS's "activity monitor" reports a very high energy consumption, so to me it's a big no (being on a laptop).
I've filled a "feedback" about that within the browser UI…
I've filled a "feedback" about that within the browser UI…
At the moment my "sweet spot" is on Opera with the "battery saver" mode.
There is some deep and dank JS on that page that makes FF loop constantly when 'idle' on that page, at least on Linux. I had to disable JS for google.com so that I could read search results without fan noise.