The Firefox portable version only runs on the Windows platform. The installer is a .exe program that install a modified Firefox version on a removable drive or on the hard drive.. On Linux you would have to run this version under Wine or otherwise via a Windows emulator or Windows installation (VMWare). Why do you want to run the portable version? The portable version comes with its own profile folder and doesn't interfere with the currently installed release version. If you install the portable version on a removable device then there are no files saved on the hard drive. Files will only be saved to the local hard drive if you would install the portable version on that drive. *http://portableapps.com/apps/internet/firefox_portable *http://portableapps.com/apps/internet/firefox-portable-esr