Onetab has proved very useful to me for some time now, but I was finally bitten by its hidden danger. Firefox (59.0.2) stumbled over something & when I exited & re-ran the browser, all my Onetab data had disappeared. I do take nightly backups, but when I followed the only advice I could find from Onetab (to replace "store.json" in the jetpack tree) nothing changed. It was only when I discovered 111byte's posting in this forum that I learnt that Onetab data is actually stored in "storage.js" in the browser-extension-data tree!

Even if Onetab's authors don't improve the way they handle backups, I hope they at least update their info on where the data is kept. Onetab is an inspired add-on, but it is in real need of the updating it's authors are continually promising. Thank you for the contribution, but you really need to communicate better with your users.