/Volumes/YOUR_USB_NAME/Firefox.app/Contents/MacOS/firefox -profile /Volumes/YOUR_USB_NAME/FirefoxProfile Use code with caution. Replace YOUR_USB_NAME with the actual name of your drive. 2. Use Third-Party Wrappers (Legacy)

Get the standard version from the Official Firefox Download Page .

In the past, developers created "wrappers" like . While some sites like Softonic or MacUpdate still list these, they are often severely outdated (Version 3.6 or similar) and pose significant security risks.

If you need a privacy-focused browser that is easy to keep "portable" or separate from your main system, consider these modern alternatives:

Copy the Firefox.app file directly onto your USB flash drive.

On that same USB drive, create a new folder named FirefoxProfile .

If you want to run Firefox from a USB drive or external folder with all your settings preserved, follow these steps: 1. The "Manual" Portable Method