https://www.pcgamer.com/firefox-has-lost-46m-users-over-the-last-three-years/

"You can have any color browser you want, as long it's Chromium."
  -- Henry Ford

While Chrome has grabbed IE's market share Google has replaced MS as the villain du jour.  Perhaps this will save Firefox; it is the only viable alternative that Google doesn't have it's fingers in it's code.

That said, the open source Chromium is really a fine browser. 

It is. I'm on a non-Chrome Chromium browser right now. But it becomes a strange form of diversity and though I am contributing to the problem, it makes me feel guilty about it.

I use Chromium most of the time I'm using the Pi desktop (and that's most of the time I'm working these days).  I do try to get people who use Edge or Chrome to consider using Chromium instead.  It has virtually all the same rendering but lacks the spyware.

>> Edge

I have used it minimally and have not really looked into what level of tracking it allows and so forth. Win10 is constantly telling me that if I switch it will search the web for the best prices on stuff I want to buy to make shopping easier. My thought: no, that's precisely the wrong solution to the shopping problem!