Did they fix the memory bloat on Mac OS? It’s pretty much useless to me on MacOS.
Haven't noticed any memory bloat myself though (= it consumes a lot of memory, like any browsers). It's somewhere between Safari and Chrome.
The thing is, Chrome actually feels snappier than both Firefox and Safari when I am using it, probably because it's profile is empty (almost no extensions, no history, etc.).
I rarely see broken websites, with any browser. And usually it's because of my ad-blocking extensions. Google websites are slower on Firefox, but rumours are saying that it's almost on purpose… (one more reason to not use Google products like Chrome).
It's night and day on some pages, like google docs word document, for example.
PS: this one is about power\cpu usage though. Never really had any memory problems on my macs.
On my 2017 MacBook Pro with touchbar I don't notice the performance hit, but on my 2015 MacBook Pro the whole system freezes with Firefox. What completely solves this however is enabling 'low res mode' (right click app icon -> get info -> check the low-resolution checkbox). But, as the name suggest, Firefox now runs in non-retina resolution. It looks crappier, but I still prefer it to other browsers.