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.

Using this plugin is much better and easier than creating profiles in Firefox manually, because instead of having to open a new window for each profile, with this plugin you can view different profiles in a single window.

This greatly minimizes memory usage (up to 5 times less).

Browsing between profiles is much more intuitive and organized, as you can distinguish each profile by the color of the tab and identify the name of the profile that is displayed in the navigation bar.

This plugin is without a doubt the best profile manager currently available in all browsers I have used.

I've been using containers since they first came out. I totally love this. I can isolate my banking and financial activity on a Banking container tab, and keep my work activity kept inside a Work container tab. Nice.

The only thing I'd been wishing for was that I could have a default tab assigned for when I open up Firefox.

The beauty of this add-on, is that I can assign containers to specific websites, and every time it comes up, I no longer have to click on a URL then either move the URL to a container tab already opened (default is no container), or open FF and open a container tab, then paste in the URL.

Now, when I go to a bookmark, it's one & done. You even will get a message for one you've recently assigned a tab, asking you if you want that to be the default tab for it. Perfect. Highly recommend this as well.