So as far as i know, firefox is the only mayor browser not based on chromium. Also, firefox is dependent on google's funding because of a search engine exclisivity deal. So my understanding is that, if google decides to kill firefox, they could easily do that. Well, what then? Is there any other browser left wich similar features that would be untouchable by google?
Sort of. Netscape released the program's source code and Firefox used that as a base, but it wasn't like they took Netscape and just changed the name to Firefox like your comment implies. They were competing browsers for a while.
They couldn't kill Firefox without having the US government come down on them for monopoly. Which the government is already looking at https://www.cnn.com/2023/01/24/tech/doj-google-lawsuit/index.html , so it's not likely Google will risk it even further by shitting down funding to Firefox. Pretty sure they'll point at Firefox to claim they're not a monopoly.
So the lawsuit appears to be looking at Google as a search engine monopoly, not web browser, right? And if I'm understanding this right, assuming this lawsuit goes anywhere, it would actually incentivize Google to pull funding from Firefox to no longer support that search engine exclusivity deal.
Google still benefits from having Firefox around, so that they can maintain less of an appearance of a monopoly in the browser space. Whatever way they fund Firefox, it's still to their benefit to do so.
This should be the top comment, and I'm going to come back to view the replies. I can't personally think of any realistic alternatives. Someone further down posted a link to an article about the US investigating Google for a search engine monopoly, but I'm not sure how large a role that would factor into web browsers.
You have to decide for yourself if those browsers have the features you need, but just for your interest, other non-chromium browsers are Ladybird, NetSurf, Flow, Pale Moon, Basilisk and K-Meleon.