well

That's a very nice addition to this (relatively) new addition to FF. Works like a charm and does what I want it to do. One thing that bugs me aesthetically is that the open new *container type* tab button("+" symbol) isn't centered in its box on hover. I can provide a screenshot, if needed.

One thing I'd want though is that there would be a hotkey to open tabs of certain container type.
Not sure if it's applicable to this extension or this whole Container feature.

Hace todo lo que buscaba en tgm pro en firefox 57

I like this addon. One thing I noticed is that there is some problem with the counters of currently open tabs per container. For example, if one opens, from the addon sidebar, a new tab under a container that has no open tabs and immediately closes it, the counter stays at (1). If one opens, say 3 tabs and closes all of them, the counter stays at (3) but changes to (1) if after that one opens another new tab.

I was struggling to make use of containers before this extension. Having a visual overview of your containers and how many tabs are active in them is incredibly helpful.