I call this bundle Izzyfox, and it has many cool tweaks and other goodies like automatic ads blocking and other speed improvements. Just drag the Firefox icon to Applications folder icon, and here you go, now you have a portable Firefox in your Apps. dmg file, then click on it in your Downloads folder. By the way I also have portable browsers available in other languages and for other platforms like Windows, so go out check my site if you need them. If I will be forced to use a password, the password will also be published on my site. There you will find a link to the latest version on Mozilla Firefox Portable at my cloud storage. Go to my site by following the link in the description.
You are all set now, let’s get the portable app. Now switch “Allow apps downloaded from” to “Anywhere” and confirm you actually want to “Allow from Anywhere”. Click on the small paddle lock icon below and enter your admin password. To enable unknown sources, you have to go “System Preferences” of your Mac. Enabling them back requires administrative privileges, which the majority of Mac users will never do, so most folks have stopped releasing portable apps for Mac.
Unfortunately, starting from Mountain Lion, Mac OS has unknown publisher apps disabled for installation by default. So you want a portable browser on your Mac?