Doesn’t half (or more?) of the discussion revolve around the fact that Firefox isn’t shipped with any product? We have known for literal decades that most folks will not change what the OS ships with. This was part of the Microsoft monopoly issue, yes? Now we have it with them again, and Google. Apple is a little more complicated I guess.

Firefox works fine, bit of isn’t part of any major package, and not all websites test for it. I don’t know what Mozilla can do to overcome this.