Very useful, it allows loggin on differents accounts to the same service (ex: two gmail accounts). It helps limiting the tracking and is easy to understand with the default categories.

A great tool for dealing with multiple web accounts. They finally added sync, which means this is now feature complete! Awesome! Please don't ever drop support for this!

Its very useful. Thank you so much.

Great extension, the ability to open a site in its own container makes it almost perfect. One thing that still lacks is the ability to sync settings between firefoxes installed with same account.

This addon is really useful. It helped me manage my personal, college and work accounts without constantly signing out of one and signing in to another. If you have more than one account for the same thing I recommend this add-on.

Works!

Does what it says and I LOVE it, I have multiple accounts to manage and with this addon I can keep everything organized and don't have to stress with multiple browsers

Very useful tool to use multiple accounts in one service.
Better than private tabs for using services and prevent cookies tracking.

This add-on stops my Facebook and Google account from showing everywhere outside.
It would be helpful to remind users that it does not work when Private Browsing is enabled, since there are some people who enable Private Browsing all the time.

Very useful for privacy and security

I am a software architect, and quite often need to login to multiple sites with different logins, including Google to segregate between work and personal accounts. I'm in love with this add-on (have been using since its test pilot days). Very helpful!