Super pour ne pas être espionné d'un site à l'autre!

Indispensable. I can't imagine going back to a browser without containers. If you have more than one account with almost any provider, the experience is much better with containers. Also, check out the "always open in" feature -- very useful if you use containers for isolating sites like Facebook.

Awesome add on!!

웹 개발에 매우 유용합니다. 여러 계정으로 로그인하여 테스트를 할 수 있습니다.

Very handy!

Container tabs are wonderful. No more testing with multiple browsers, no more private browsing which share the same cookies! I really enjoy browsing freely on different websites, saving cookies but don't sharing them.

allows me to separate my cookies without worrying about contamination

It should be included by default in every browser. I only wish there was an option to synchronize my config across different computers.

This is really great idea man!

Good

Very useful for keeping my information safe. This removes the need of having different browsers open and helps maintain the cookies I use.

Excellent for organization and privacy. Use it everyday

Works great and a it's great way to organize tabs. I would *love* if I could save a group of tabs in a container to bookmarks.

Good

This is a game changer. I loved Firefox in the past, but really had trouble coming back. The containers are amazing for many of us concerned about privacy, security, and organizing our online lives. These have made Firefox, once again, my go-to browser.

Definitely one of the indispensable extensions if you have multiple accounts on some sites like me. It works exactly as expected, fast and elegantly designed. If there’s one minor thing I still wish, it’d be showing in history which container each entry belonged to.

Great addon for those who need to access same service from several distinct accounts. (e.g. Google developer console)

My favorite part of Firefox!

I've really come to depend on the multi-account containers. It's a much better alternative to using profiles for managing online accounts.

@Albert Kolkin:
I use it with multiple gmail accounts. The secret is to press and hold the "+" button so that you can select the container that you want to use. Then you can go to gmail.com using a bookmark for example. Since there is only one url for accessing gmail you can't use the always open the bookmark in a particular container feature like you were trying to do.