Realistically their business would not be able to function without tech giants funding it. The only reason those tech giants fund it is to both continue to promote their own products and to reap the benefit of arguing that it is to foster competition. This is a longterm no-win situation for Mozilla.

I guess I could see government drafting bids for developing browser technology (make a national security argument like this stupid bill does) that Mozilla would be able to win. Of course then we'd have articles written by people freaking out about government influence.