Google knows that every time they release a Firefox bug, FF's user percentage goes down a tiny bit. Repeat over dozens of bugs, for years, and you have a strategy.
There's one blog post from another Mozillian that I can't find anywhere that came out within the last year with other examples, I think it was on HN.
You are looking for https://web.archive.org/web/20180728122724if_/https://twitte...