First: good idea. But there is no such thing as being able to "sort" the container folder. I looked everywhere.
Second, I created new tabs under the provided option, but I do not have or see the option to create a new one when I rightclick to see the container with all tabs there.It does only show "re-open a container. I don't want to reopen but create a new additional one.
I have right no pages in any tab because just installed the multi container addon.
Howand when does the option "to create a new tab" show at all?

Maybe I don't understand the concept. Should it not be able to be handled similar to a bookmark or save the tab?
It's not very clear from the writeup for options.