While the extension is incredibly useful, it has some glaring omissions.
For some inexplicable reason, once you set a container as default for a website, you can never clear that default again, at most you can change it, but if you have multiple containers for different accounts on that same website, whenever you are browsing it and want to open a link in a new tab, it will always, at the very least, prompt you to open on the "default" container, which is incredibly annoying.
Another incredibly annoying thing is that you can't truly sort your containers, they will always be on the order they were created. And whenever you reinstall Firefox, or install on a new device, and need to reinstall your extensions, including this, the containers will again, be in the same order they were created, and even if you sort them to your taste when clicking on the extension icon, in the "Open Link in New Container Tab" context menu, they will always be in the wrong order.
Please fix this, devs.

Really useful for when you need it. But if you ever use the "Always Open This Site in..." feature, there's no intuitive way to make it open in a non-container tab. You're stuck with that shit forever. I'm so incredibly frustrated with this.

There needs to be a list of sites. i have a site stuck in asking me what to open it in and even when i tick remember my selection, no change.

It'd be nice to be able to open in a new tab based on URL matching, not just domain

It's a great idea. I love how I am able to "contain" cookies to certain domains. The only issue I have is that some login pages does a lot of redirecting (bing, google, et. al) which this extension doesn't also capture. There is no way to add domains manual or wildcard certain subdomains. It the extension does see it you can't "fix it". The only work around is to turn off "limit to certain domains" but that is a pain to toggle back on and off when you need to login and such.

The extension is useful, but a basic and very important feature is missing. I request the developers to add tab grouping. So that the grouped tab got hide within the parent tab like personal or work tab groups.
thank you.

1. No ability to separate site list by a part of URL, for example google.com vs google.com/maps.
2. Leaves a phantom open tab when using a custom new tab page extension every time you open a new tab, if your search engine website is in a container and tab behaviour is not set to "replace".
3. History is not shared between containers if tab behaviour is set to "replace". So I need to press "Reopen closed tab" if I want to go back? Not the best UX.
4. Desperately needs "create a new container for this website" feature.
5. Needs more colors and icons.
6. Firefox settings menu has a separate Container Tabs setting, which has a different set of options compared to this extension. For example it has an additional color set, which will appear as black in the extension list. Very confusing which ones are which.
7. Numerous bugs like being unable to open a page in "No container" if that website is already assigned to a container etc.

I use containers as a separation of work areas so that I can switch between work and entertainment so that unnecessary tabs don't distract me. Containers don't do that well!

1) I want the containers to be easier to hide. Right now the interface is complicated, there are a lot of clicks.
2) It's not clear why a hidden container drops me all the tabs in it if I add a new tab to the container. I just want to add a tab, not open 100 tabs I don't need!
3) I see the concept of containers as switching different desktops. So that they don't mix with each other unnecessarily.
4) Tabs outside of containers. There should be a setting that specifies what to do with these tabs: either hide them when any container is open, or leave them parallel to the container.

I've been using this addon for a while and it has been great! The last 3 weeks it has been asking me which container I want to open Youtube each frickin' time I visit Youtube. I haven't found a solution to this, so this lead me to uninstall the addon.

I just can't figure out how to always open a site without a container. "Remember my decision for this site" seems only works for containers, not no container.

Please make it work right ... This is a great idea and would work fabulously if someone finally added the ability to specify ROOT DOMAINS, like *.google.com instead of fighting with the add-on and adding each host a site uses, one by one, by hand. Even Cookie Autodelete can handle this. The last missing piece from this add-on. Could someone FINALLY make it work? ;-(

Great start, but few things that are broken in an annoying way. For example, "Remember my choice for this website" never works if you select the non-highlighted option (no container). Also there's no way to edit or change these defaults once you selected them if you're not a developer and you're not ready to dig in the local storage of debugging the addon view.

It was working really well, I have multiple MS and AWS logins and I used this to enable multiple login sessions in different tabs. I don't know if MS have changed how the sessions are identified or an update broke it but it no longer works, I'm back to opening everything in private browsing sessions... Boo :(

This COULD be really really really good, but they need to put some thought into it, and it looks like they once did but removed some of that due dilliigence in the Great Firefox Rustification, because you used to be able to reset a site's "Always open in" association by right-clicking anywhere on the site, but now, I have zero f*** clue how. And if you set a site to always open in a container, and now you have to login to a different account that logs in with Google? Well Good luck bud. Use a different browser, and just hope you don't need 2FA from a client who's in a meeting I guess.

Not the best... It takes too long to open every time the proper container before open a web page. I wish I could link up every single url to the specific container and make bookmarks of it. So this extension is just half-productive.

What unholy alliance has Mozilla/Firefox entered into that they do not have a Android version?
When they do provide a Android my rating will go to 5. Come on Mozilla, I have 2 two Shiney Gold Stars for you.....

Great plugin, use it all the time, but has developed a nasty habbit of NOT remembering my choices about "always open in xx tab".

There are a lot of great things about this extension, but there are a few things wrong with this extension:

1 - Reordering the containers via Manage Container does not reorder the context menu when clicking on a link which you want to open a specific container.
2 - The Ctrl + Shift + # shortcut also does not use the same order, which makes the shortcut after reordering containers totally useless.
3 - Urls with paths cannot be assigned to default containers, making them very hard to use with sites that have the same root, but different authentication per path (which you thus want to open in separate containers).

These issues already exist a long time (and looking at the VPN stuff that is being added instead of fixing these) this extension will probably never work any better..

Which is a shame, because its a killer feature.

I love the idea of this add-on. It is a browser-defining feature that is a big reason why I am a loyal Firefox user.

But, it pains me to write this--Multi-Account Containers is _extremely_ buggy. The add-on crashes constantly (closing all of your container tabs and deleting all your custom containers), sometimes containers are mysteriously duplicated hundreds or thousands of times, sometimes it forgets which sites are assigned to which containers (forcing you to reconfigure them). At one point I had to delete my Firefox account, losing a paid subscription to Mozilla VPN, because MAC had corrupted my sync settings. BTW there are >700 open issues reported on GitHub: https://github.com/mozilla/multi-account-containers/issues.

But--despite being a buggy mess, I still love this add-on for what it does when it works, and for what it could be one day. So I can't give it anything less than 3 stars.