I've been using this for a bit on Nightly, and though I'm wary of sacrificing website screen real estate to the browser, I must say that I found out that I'm using the new buttons quite often. Or rather, I had been using them a lot via the menu, and it's actually pretty nice having them easily available.

Turns out I use the forward button a lot because I've enabled gesture navigation, and often accidentally move back. Ironically I use gesture navigation to save on screen real estate, so maybe I should stop using that 😅

Other than that both refresh, share and new tab are in very heavy rotation, and it now feels like a slog to have to open a menu for them. I say, give it a shot!