First I thought this finally works, on Linux. But frequently my Tabs disappear, new windows being opened instead of the old one, suddenly I have several windows open, and when I transfer tabs from one window to the other, after a while the whole panel where I dropped it into, vanishes. What good is the use of a program that causes you to do lot of work grouping and arranging and sorting, when it frequently causes loss of data? Snapshots have not done the trick for me, it just gets more confusing when it just opens more windows. Updating Firefox causes loss of all tabs. Erasing a part of the browser chronic through Firefox (just one page) causes loss of all tabs. Is not sufficiently integrated in Firefox on Linux in my opinion.