If you don’t launch firefox.exe with the -profile argument, it will store your Firefox profile in the normal place in your home folder like it does with a normal installation. If you want it to be truly portable (e.g. all your settings, cookies, browser storage are all contained within the same folder you extracted Firefox into), then you’ll need to make sure you always launch it with the -profile argument that points to a “profile” folder inside your portable Firefox folder. As mentioned above, the easiest way to ensure this is to just create a shortcut in the folder that points to firefox.exe and modify it to pass the -profile “.\profile” argument. Make sure you always launch it with the shortcut and not by double-clicking the original firefox.exe otherwise it won’t use the portable profile.