Excellent idea, besides for security/tracking reasons it is very useful to efficiently manage multiple often-conflicting accounts that get on your way when you work (Google accounts, for example).
I would improve the following:
- possibility to reorder the containers
- instead of (or in addition to) long pressing on the '+' it could be nice to have the "top 3" containers inlined as '+' buttons to open a new tab
- perhaps custom icons for the containers? If it works well

I've been using this Add-on for few days now but I already love it if it works in pair with Ghostery it's falwless combo

It does what it says, and this helps immensely on maintaining ones privacy online.
The best enhancement that can be done is the addition of synchronization of my choices, preferences and configurations on this plugin.

Faz o que se proõe a fazer, e isso auxilia imensamente na manutenção de sua privacidade online.
A maior melhoria que pode ser feita é a adição da sincronização das minhas escolhas, preferên e configurações para este plugin.

This add-on is promising, but is useless to me without the ability to sync preferences.

Полезное расширение.

Love ur open source thing.

This add-on does exactly what I need it to do. I have three profiles setup (for three different Google account) and use it to open certain websites with the appropriate profile. It is nice being able to have different profiles share the same window.

It would be nice to have different shortcut keys for opening new tabs in different profiles.

yooooooo

I love the idea, it works really well to separate environments, like separate google and facebook, or have two separate google accounts.
It lacks an important feature: not sharing history between containers.

ótimo para várias finalidades: separar uma aba 'comum' de uma pessoal* e separar dados de sites bisbilhoteiros são as mais úteis... *útil quando sua mãe pede pra abrir nova busca e você não quer um monte de bolos no seu histórico...

makes my work way more easier

Love this idea. Hopeful that other means of fingerprinting can similarly be obscured (IOs Safari's new tools seem to show promise), but this is a good tool--thanks!

Excelente! Es lo que estaba necesitando

Great extension.

topkek really helps with signing in into different accounts, although you can only be signed in into one account at a time per website. still wish that the profile feature in firefox were more like chrome's

Very safety

With this I can still use accounts with privacy-unfriendly companies when I want to, without being logged into them all of the time, and without juggling private sessions. It also lets me keep around multiple sets of settings for any given site, which means I can migrate away from old accounts at my own pace.