Rarely does one find add-ons or extensions that become so integral to one's workflow that it makes it hard to use other browsers. For me, this is one of those add-ons. If you like to organize your tabs around tasks, topics, or projects, this add-on in indispensable in being able to quickly task-shift within a browser. It's interface clean, easy to use, simple to understand and customizable. It also plays nicely with containers for the ultimate in separation of concerns. Thank you, Tomasz, for creating it; it's very handy.