Currently, Google pays Firefox’s bill by having them set their default search engine to Google.
This will no longer be when Chrome is in the hands of another party. DOJ is currently advocating for this forced sellout.
So will Firefox be no more after that?
Quite the opposite. The death of Mozilla Corp will drive the community to greater heights. I expect to see Floorp, Librefox, and even Basilisk/Pale Moon having a voice in the conversation of post-MozCo Firefox.