I'm going add a controversial opinion. I've been using Firefox my whole life but recently I'm finding Safari to be a more appealing option than both Firefox or Chrome. Firefox, and Chrome to an extent, are powerhouses. They have a great community with awesome and really creative extensions. Safari only just started adding extensions and it shows: apart from the usual ad blocker stuff, there's not much out there. But…
It seems as though the world is moving to an 'appliance' plus app-store model. In that world the browser is part of the appliance and considered part of the purchase by the consumer. In that world, the only way for FF to have a presence is via hardware partnerships.
Yet another FF alumni alludes to the threat in a comment on the 'Chrome won' post [1] (my emphasis)...
"...for historical reasons Web sites targeting large-screen non-touch devices tend to configure themselves in a more standards-friendly way. ChromeOS is changing that; it has the form factor of a desktop platform, but not the third-party browser viability. If Android expands into that space, or Windows and MacOS get locked down a lot more, then that also closes up the window for Firefox."