Very good! But there are some bugs:

If you are in a container, Alt+Enter (in the address bar) should open the url in another tab BUT IN THE SAME CONTAINER as the currently selceted! Currently it opens the new tab in an empty (non assigned) container. This is troublesome specially when the desired new tab depends on the current container (session cookies, etc)

Another bug: If you edit the color of a container while already having open tabs from such container, the color of those tabs doesn't change (but the color of the icon in the address bar does change).

If you open new tabs with the edited container, they do open with the new color. which may lead to confusion having several tabs with the same container but different colors.

Please fix the bugs ASAP. Thanks