作者： Keefe Dunn

Seriously, there’re times when you need to run different Firefox instances with respective profiles. If you ever encountered one of the scenarios below, you probably need to read this.

The Reasons

1. You need to store different cookies for the same website. (What is cookie?) As to myself, I’ve got two Google accounts, and I want Firefox to remember both of them.
2. You share your computer with someone else.
3. Since the more addons you have installed, the slower Firefox becomes. Using separate profiles, you can install plugins for specific tasks in each profile.

The Solution

There are instructions on solving this problem with the Profile Manager plugin, such as this tutorial by Ross McKillop. However, what I’m going to describe here is a simpler solution.

1. Modify the shortcut to firefox.exe. Mine had an argument "-profile ‘path\to\the\profile\folder’", then I added the argument "no-remote" and it became "-no-remote -profile ‘path\to\the\profile\folder’".
2. Create a new folder where fits, which will be your new profile container.
3. Create a new shortcut to your firefox.exe with the command line arguments "-no-remote –profile ‘path\to\the\new\profile\container’".

All set & start to enjoy two Firefox instances at the some. You’ll see that the whole point of this method is the command line argument "no-remote", which enables Firefox to run with multiple profiles. You can find an incomplete list of Firefox command line arguments here.