I’ve now upgrowed (new strong past tense of “upgrade”) to Waterfox, a true 64-bit browser.
It’s a little bit slower at day-to-day usage according to benchmarks, but nothing I can notice. It has no 2GB process limit – which I often exceed – so now I can use all 32GB of memory and not have slowdowns when I have more than few dozen tabs open for a while.
I told ya’ll I’m a heavy user.