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.

Una maravilla de extension, antes tenia que abrir diferentes navegadores, ventanas en modo en incognito pero ahora con esta no hay necesidad de eso, ya no tengo que salir de mi amado Firefox

works great for me! i just wish there was more color options for separating specific sites, like not having Ebay and Amazon on the same shopping container, but a separate one which can be recognized by a separate color

Awesome plugin. Thanks for thinking out of the box!

This, combined with Cookie AutoDelete is fanastic. I can keep suspicious sites (and services) isolated from things I care about. With Cookie AutoDelete, cookies I don't want are erased when I close the container. It is a lot like "private browsing" or using Focus on a cell phone / iPad with some advantages. Login cookies can stay alive until I totally close the browser.

Highly, highly recommended.

This app along with the profile options (firefox -P) make the ultimate combination for privacy oriented people.

Keep up the good work Mozilla.

It's one of these things that you didn't know that they exist but now you can't imagine your life without them. It will make you feel pity for your former self. No more logging in multiple browsers to handle multiple accounts on the same domain.

Really useful while developing sites which needs backend and frontend tests with separated cookies, sessions, etc, separated.