Very nice and usefull, it reminds tabs after closing, and can manage it with the native mozilla groups, just add please shortcuts and correct a bug that sometimes idk why when closing it moves some tabs from one workspace to another.. , but before closing it works perfect

do not work after restarted browser and also after closing window

If you close the browser it didn't remember the tabs that were open. I wish that it would have a feature that let's you change workspaces with keyboard shortcuts.