Handy, I put mind on an iPod…Cross-platform Portable Firefox works by using John Haller’s excellent Portable Firefox 1.0.6 on the Windows side of things, and a little script I made on the Mac side of things. The script basically keeps two versions of all user profile files. The reason why is simple: as I am sure some of you have figured out, Windows Firefox profiles are not completely compatible with Mac Firefox, only certian files. Link.