Multifox Addon

All of the scripts on this site are using the following software Mozilla FireFox iMacro GreaseMonkey MultiFox You will need to download and install all 3 of these. Going that route allows Multifox to function again. I agree that add-ons are the responsibility of the developers, but sometimes asking firefox experts is the key. Multifox changes all of that, allowing you to set different accounts to be managed by Multifox per tab, where the accounts don't interfere with each other. Multifox allows you to assign an identity profile to each tab and isolates them from the rest. Each identity profile starts off as a number, but can be renamed to anything you want. Next, download the Multifox browser add-on for Firefox. Disclaimer: DO THIS AT YOUR OWN RISK. If you do it, I would suggest uninstalling it as soon as you finish the game as it's an unlicensed add-on.

2014 is in full swing, and so is our community board, which has selected the featured add-ons for February. If you have an add-on to nominate, please send it to amo-featured@mozilla.org for the board’s consideration. Feel free to submit your own add-on!

Pick of the Month: Multifox

Multifox

Multifox is an extension that allows Firefox to connect to websites using different user names, simultaneously! If you have multiple Gmail, Twitter, Facebook, or Yahoo accounts, you can open them all at the same time. Each Firefox window accesses an account without interfering each other.

Awesome! I can log multiple emails, gaming accounts, forums, proxies, and so much more!”

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Multifox addon
Some time ago, we talked about CookiePie, a Firefox add-on which allows you to use a new session so that you can log in to the same service with multiple accounts (such as multiple Google accounts, etc). But CookiePie doesn't always work and it breaks the cookies if you move the tabs around.
Multifox is another Firefox extension for logging in to multiple accounts on the same site which I like because it doesn't messes with your cookies and I was never logged out from both accounts like it sometimes happens with CookiePie.

Multifox works by adding an entry to the tabs context menu called 'Open in a New Identity Profile':

Multifox Addon

and by clicking this, a new window will open so you can now log in to another account. The new windows will have a number displayed in the URL bar:
Addon

Multifox Addon

Install Multifox (don't worry about the site being in Portuguese, the add-on is in English).