Installed, clicked it, lost 100 open tabs.

ADD-ON IS BROKEN!

Lost my tabs two times in a row now..

Author kill youself! WTF where is easy ability transform all the pages from one to many?? I los a lot of time with you raw stupid app.

纯纯垃圾

It doesn't open anymore

這是一個簡單易用的好東西，
直到Firefox大更新前都是。
今天大更新後，我的資料被清空了，
嘗試許久也救不回來，
是時候，該放棄這套工具了。

這套工具幫助了我許多年，
還是謝謝你作者。

No cloud or sync

All of my saved pages randomly disappeared.

Não pede confirmação para remover todas abas atuais, para agrupar em uma aba/página com os links. Deveria ter essa opção de configuração, inclusive a confirmação para realizar esse processo de agrupar os links de abas em apenas uma aba DESTACANDO que as abas serão fechadas.

DO NOT INSTALL THIS. It will delete all of your tabs, with no way to recover them. Check the other reviews, this is happening to everyone.

Don't use it, it's very great at first and then it will lose all your tabs. Twice.

Has worked well until recently, but now all my tabs are gone and I see I'm not the only one..oh, and their instructions for recovering lost tabs is a joke.

tout est perdu : nul !

OneTab Team, have you never heard of user-level queries or safeguards?
This add-on desperately needs them, and hopefully you're clever enough to figure out the rest by yourself.

OneTab has been around for so long now and it still feels like just a proof-of-concept type of add-on. It's missing options and features, and it seriously needs some kind of overhaul with a focus on performance when handling more tabs & groups.

Have lost all my saved tabs multiple times after my browser updated. Do not recommend at all.

lost all saved tabs after a browser update

Leider werde ich OneTab nun löschen, nachdem in der Vergangenheit mehrfach meine gespeicherten Tabs verloren gegangen sind.
Schade.

I don't see why it may be useful

I had 500+ tabs and did the mistake of clicking this extension. I have another extension (Panorama View) which grouped them, but OneTab discarded all of that. I tried reopening them all, but Firefox crashed, and after restarting it, all of my tabs were gone. Oh well.
TL;DR: I lost every tab I had.