Great Add-on!!
Nice to tidy up and organize Tabs. I like the possibility to easily separate websites, which shouldn't get in touch.

Just needs some additional configuration-tools +sync!
-rearranging containers, inclusive default (as I need it), is a must have! (I need default Tabs at the end)
-Pages in a container+settings(like always open in container X) have to be synced to other firefox-devices!!
-also to android
-more symbols colors
(- Advanced Options)
These point are not given at the time I reviewed it!

..would be nearly perfect, improves my experience a lot!
I really want to give it 5 Stars!!!