> I like FF. I use it. But every time there's some comment
  > about FF memory, we usually see a bunch of people coming
  > out saying they never see FF memory issues, the OP must be
  > doing something wrong or have a bad system, they use their
  > computer non-stop for 4 years without ever even seeing FF
  > slow down, etc.

That's because complaints about large memory use in Firefox fall into two camps, generally:

1. "I left Firefox on overnight with three tabs open, and now it's using 3.1 GiB of memory. This browser is terrible! Yes, I do have dozens of low-quality extensions installed, so?"

2. "I started Firefox, and already it's using over 300 MiB! That's insane! Why would a web browser ever use that much? I'm switching to Chrome, it only uses 100 MiB. What do you mean, 'multiple processes'?"

There may in fact be genuine issues buried somewhere in the discussion, but they're hard to discern against the general background noise.

  > Then endless discussion about "how can you even function
  > having more than 2 tabs open? I always close all mine
  > because of some cognition study from 1974 which I read in
  > my one open tab, then closed it".

You're getting confused between Firefox and Chrome. Firefox has always been the browser of choice for the "tons of tabs" crowd, because Chrome's process-per-tab model breaks down when there's more than a few dozen open.

For example, I have just over 70 tabs open right now, Firefox has been running for about a month, and it's at 1.1 GiB resident memory. Chrome becomes very unhappy under such circumstances (since it uses about ~100 MiB per tab), so I'm careful to only open a few tabs at a time.