Both Chrome and Firefox seem to use slightly more battery than Safari on my 2016 MBP. When I say slightly more, I mean that according to Activity Monitor, they both have ~3x more "energy impact", however in practice I haven't noticed a difference in my battery life.

The major difference with Firefox is that on some websites (namely Google Maps, Youtube, Twitch, sometimes Gmail), Firefox spikes my CPU usage/temperature/energy usage to absurd levels (I'm talking 90+ degrees celsius), so much so that I find Firefox unusable because I don't enjoy having a brick of near-molten aluminum in my lap whenever I watch a Youtube video. Chrome and Safari don't seem to have this problem.

Cool danke. I'll give it a go then, the only thing I hit of those is youtube. I've been migrating all my stuff off gmail to fastmail so I'm pretty good to go in that regard. Energy impact in activity monitor is ok...ish but in the end I normally look to the actual battery percentage.

If its in spitting distance of safari it'll be ok, i'm a pretty hard user of tabs though so would be nice to get back to tree style tabs. But sounds like it might be worth a go.

I'll give safari and firefox a comparison with the same tabs opened in a window and see how long it takes to get to some battery %. Chrome last time I checked with a comparison with the same kind of usage was over an hour less battery life.

But this is obviously impacted by what websites one goes to etc... so really impacted by my own usage really.

Yep, I experience the same issue on a 2015 13" MBP. Appears to be an issue w/ FF and OS X scaled resolutions (https://bugzilla.mozilla.org/show_bug.cgi?format=default&id=...)

Oof, that bug doesn't inspire confidence that this will be a worthy experiment. Thanks for the link though, I'll test against a fresh install of osx on a laptop.

Depends on what you do. I don't see much different in general browsing, but youtube takes much less battery in Safari.