Almost none of that money goes to the development of Firefox though.

That which is claimed without evidence can be dismissed without analysis.

The same thing can be said about the opposite stance you are taking. The question is: do we already know things, and how easy are the things we don't already know to look up?

Regardless, I have Googled this for you: please return the favor by helping others learn to use search engines in the future before leaving comments insinuating that they are lying.

The tldr (as you'll probably insist on that also) is that Firefox finds Mozilla, not the other way around, as the latter is a non-profit while the former is a FOR-profit, so Mozilla actually can't directly fund Firefox.

https://www.reddit.com/r/firefox/comments/ow9k0y/is_there_a_...

https://www.reddit.com/r/firefox/comments/a98gmi/donations_t...

https://news.ycombinator.com/item?id=24200395

Much of it goes to policy issues like this very one, and to government education about these kinds of things, and to other important efforts closely aligned with this exact issue. Mozilla does both "advocacy" and "product" and that two pronged fork exists to serve people and the web, not massive ad companies.