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Fantasticounzi!!! Funziona benissimo. Tanti browser in 1. top!

This is by far the best solution for anyone who wants to have separate spaces in browser storage for each part of their online lives. Now I can finally open multiple sessions to the same site and expect links to open in other sites with the corresponding online presence.
This beats the multiple browser profiles approach natively available in Chromium based browsers, because links from externals applications might not open in the correct profile. The same quirks apply to multiple Firefox profiles too. Being able to select which container certain links should always go to has solved at least 90% of my frustrations!

This is great productivity hack and helps so immensely.

EN:
Great extension, secure, from the developers themselves, open source, updated.

RU:
Отличное расширение, безопасное, от самих разработчиков, с открытым исходным кодом, обновляется.

This extension is one of the most useful things in Firefox. Pair it with Sticky Window Containers and it's perfect.

This extension is great and works like a charm, allows you to use different social media apps in different containers making it a little bit more difficult for them to track you, plus, allows you to check different email or whatsapp account in the same browser.

Not only useful for keeping separate logins and separating work/private browsing, it also is a very helpful tool when developing and testing web sites

Very practical! It's really easy to be able to separate various accounts and websites!