Their main revenue is sending search traffic to Google. I imagine a near-future source will be paid subscriptions to LLM products that integrate tightly with the browser.

Both of those require convincing people to use the browser, which is "selling" in the sense of persuasion even though there's no exchange of money at that point.

Sorry, you are all missing the point.

By "sell" I do not mena to make a profit, I mean, make it visible to the market.

If firefox did its job and got out of the way, who would notice Firefox? It is hard to sell something with no "bells and whistles". Do you think it is a mistake that Liquid Glass exists? No. LG is there so you notice you are on an iPhone which uses to just get out of the way but now is just in my way all the time.

Adding AI to Firefox is to make it visible in the market.

Your data, presumably.