Why are you intentionally avoiding the question? Tell me why a non-technical user should prefer even a hypothetical, 100%-compatible Firefox over Chrome.

Remember that they are non-technical, they aren't aware of FOSS or the history of Mozilla and have no ideological reason to pick Firefox, so the decision has to be made purely on functionality.

What groundbreaking, relevant-to-the-average-user functionality (dev tools and advanced, off-by-default privacy options don't count) does Firefox have out of the box that Chrome doesn't?

I'm not avoiding your question - I'm pointing to why Chrome is in the lead.

If Chrome didn't have Google backing it and Apple didn't mandate Safari, Firefox would likely have significant market share.

This isn't a battle over functionality, it's monopolistic invasion of an open ecosystem by giants that control all of the ingress points. They're turning the entirety of the web itself into an ad/product funnel for giants.

I don't care if Mozilla wins. I just don't think the world is healthy with two OS/mobile/search vendors controlling every major piece of technology.

The technology sector will be healthier if these companies are forced to break up. There will be more competition and more innovation as less is spent fighting for the last 1% of growth.

Firefox usurped the then-incumbent IE6 despite all odds. Chrome can be usurped likewise.

Unfortunately for the Mozilla fanbois, though, Firefox won't be an usurper a second time because as already mentioned it's degenerated into simply a Chrome ripoff.

A new competitor can usurp the throne, but it needs to be a genuinely better product to do that and Firefox today is not a genuinely better product.

I used Firefox back then because it was faster and performed better.

Then I used chrome because it was faster and performed better.

Now I use safari because its fast enough and chrome is getting creepy.

If you bother to read the research they've done it makes the case that most people never change the default browser.

That's basically how most people 'choose' their browser.

It also goes over how every other browser engine is actually a Chrome ripoff - some UX changes don't make that so.