Multifox is a popular Firefox add-on that enables you to log into websites with multiple accounts at the same time.
You will be able to browse all your GMail accounts simultaneously, for example.
Multifox adds commands to the File menu and bookmark context menu that you can click in order to create a new identity profile where you can use add your other accounts.
Multifox is cross-platform and it works on Mac OS X, Windows and Linux.
· Firefox 15 or later
What's New in This Release: [ read full changelog ]
· Compatibility with Firefox 23 (due to localStorage refactoring).