Works only for less number of tabs. If the numbers increases, it fails and all you work gets damaged. Using for around 1 year now, it crashed multiple times, but I continued using it, since I did not find anything as useful as it was. But now, I don't think it deserves my time. Productive people should avoid using it as one cannot have any idea when it is going to crash, mix few tabs from two different groups, delete few tabs, delete few groups, ruin all your work, add same tabs in a single group for multiple times and the list goes on.