>>beezle+(OP)
Firefox should go all the way on this. Exploit bugs, modify binaries, whatever it takes. With user consent of course. If the user says they want Firefox to be their default browser, Firefox is justified in modifying the operating system to achieve that. Ultimately Microsoft is powerless to stop this except by using their antivirus to block installation of Firefox in the first place, and I'd like to see them try that because the blowback would be epic.