They separate single account with multi categories, not multi accounts. They claim that categories exist, but the way to open them is difficult – click here, then here, and choose from there. They may have ideas for the future, but for now, this is my review. Best wishes

A good idea but completely unfinished.

Sync to a new browser always merges the default configuration without asking. The Sync does not sync the 'limit to designated sites' option, so you have to manually apply that to all the categories (while you clean out the merged in default configuration).

Management of the categories is woefully sub-par; how is there no way to manually add domains or wildcard domains to a category? Try keeping a service like Google in a 'limited' category and watch the SSO explode every time you go to maps dot google dot com because the browser doesn't stay on the auth redirect long enough to add it to the container though the UI.

It also breaks the firefox profiler, as the profiler can't load profiles from outside the category.

None of this bothered me when this feature was new, but it's been years. I wish I could recommend this and use it in earnest.

Offers to sync with android, but the extension is not available for android (doesn't appear in search results) therefore impossible to sync with multi account containers on Pixel 7a. Don't know how this will work with multi account containers on my laptop not syncing with my phone

As it says it in the description, it lets you keep different profiles for different use-cases. And helps avoid the cross-site cookies from tracking your activities across multilple sites. e.g. allows you to keep your shopping and social media browsing separated.
While you could do this yourself by managing multiple profiles, this extension simplifies the process and makes it easier to do so.

Add-on is in Russian and it is NOT the language of my OS nor FF. I don't see the option to change the language. It doesn't spark confidence in this add-on in current geopolitical situation.

Terribad sync, messed up everything

It's good to just be good. Pretty cool to also integrate the VPN.

Una extensión muy útil que me permite usar diferentes cuentas bajo la misma ventana y navegador de manera muy cómoda. Es una de las ventajas de Firefox 🦊🙌

Its good, but half baked. Instead of using profiles, we should be able to isolate history within each container and have default container option. Thats the only basic expectation for this extension

Does exactly what it's meant to do. Great addon for protection against cross site tracking.