Used to have this on Chrome in 2018, worked. That's why I trusted it and didn't export.
Now, in 2020 on Firefox/MacOS, didn't restore 48 tabs, but removed them from the list. Hours of work destroyed, no chance to know which 48 of ~ 1000 tabs were relevant to me.

Had the infinity Mark for over 100 tabs, and 'add all tabs to onetab' saved a grand total of TWO of them. Real useful. Beware, Android users.

Lost over 100 tabs on Firefox for Android. OneTab only saved… one tab: this very page. Why on Earth is this plugin marked as compatible for Firefox for Android?

DO NOT TRUST THIS EXTENSION. I've had it crash multiple times losing all my tabs on multiple different browsers and computers.

BEWARE! This add-on has closed all my tabs, and has populated only 2 out of the whole lot. I have lost all the tabs and there's no way to recover them.

Broken on Android! Beware! Only saves a few tabs (if lucky), I had 43 tabs, it only saved one. I tested again with twelve, and it only saved three. I was also unable to recover the lost tabs through 'recently closed' in history. Wonderful on PC, disastrous in Android.

No tengo.

Added OneTab, and it immediately closed all my tabs.
No tabs to restore.
No chance to get tabs back.
DO NOT INSTALL THIS ADD !!!

this app is broken and a risk to anyone who uses it provided you rely on it to 'save' your bookmarks. i had multiple pages saved to OneTab and one day it was all gone with no reason or explanation, and there is 0 support (completely ignored when I reached out for help, as I had some important links saved). Just bookmark what you need and give this broken app a miss!!

Closed out of all my open tabs, with no results. I used it on note 9 with firefox

The worst add-on I had on my system for months. Had the same running in Chrome, where it works quite well. On Firefox (72.01, 64 bit) win7 64 pro, it let me lose more than 250 tabs collected over a long time. Hope to retrieve them in my backups, but this add-on should be taken of the list immediately. One star is still one too many.
If the developers want to keep a small fraction of credibility, they should publish a method how to retrieve the lost tabs yet today.

Totally screwed my tabs and session on FF Android.
FU OneTab, specify if you know it's not working on Android.

I NEVER post reviews, so you know it is BAD when I'm forced to. Onetab crashed my browser and now I've lost months of research. I just installed the add-on, while I had over 1250 tabs in my browser. After installation I clicked on the icon, thinking it would pop open a selection window like many other add-ons. NOPE, Onetab closed ALL my tabs, which is not what I wanted. I saw the option to restore all so I selected that. It reopened all tabs (1250) but as you may know Firefox cannot handle opening that many tabs at once and it hung Firefox up. I gave it my normal 15 minutes to see if it would recover, it did not so I had to do a forced power off reboot. I've been using Firefox for almost 20 years, so I deeply understand how it handles the hundreds and sometime thousands of tabs I will have open for my research. Of course you can never reload all tabs at one time as when you have to many tabs active it slows down or crashes Firefox. So I reboot my machine once per day or after working on several hundred tabs. When it reopens I can go to the tabs I need to continue work on and only those will open.

After the crash, Only the Onetab tab was open, my 1250 tabs were gone and the Onetab showed no saved tabs. I tried using the standard Firefox "Restore All Tabs" function and it only opened 24 of my 1250 tabs, the rest were completely gone. I tried going to my History and copied all tabs from the last 7 days, but got 3,654 tabs, and I only worked on maybe 300 tabs in the last week. I then copied all tabs from the last month and got 7,359 tabs. While I've never copied tabs from the History section I've never seen numbers like that. I backup all tabs once per week to a bookmark file. When I copy all tabs from there it is always the exact number I have open, in the case of last weeks backup it was 2,641. Last week, as normal, I see it is that high and I go and close as many old research tabs as possible, so that is why this week it was down to 1250 tabs. But not Onetab, while a great concept has cost me the lost of one week of work. I could spend the entire rest of the day painfully going through the last weeks history and reopening every single lost tab, one by one, but this is so painful and I loose another full day of work.

UNINSTALLED, yet another Tab Add-On that causes crashes and corruptions, beware, if you use more then ten tabs as once, DO NOT INSTALL THIS ADD-ON.

Not working on Android at all, only my tabs were closed, remove this trash out of Android platform!!!

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Have read those comments related to Android now, and there are even many more 1 star comments which are of desktop platform, so it's unbelievable why this f**king VIRUS is still here when it always make frights to its user?!
and when its developer team seems dead?!

I am so mean to try this again and to have any wish on it. Damn!

This addon has literally killed 100+ tabs beyond any possible recovery. I have read now the 1 star feedbacks; I should have read them before installation and shouldn't have installed an addon which is more a VIRUS than a tool. I invite all users to report/ complain about the addon because of a major security issue. This product should be banned.

Beware !!! OneTab took my bookmarks and scrambled them. All out of order now with lost date, too. OneTab took my tabs and made a list. When I restored them, 1.) IT PUT THEM BACK IN REVERSE ORDER, 2.) IT OPENED ALL MY TABS WHICH TOOK HOURS TO FINISH OPENING 3.) ABOUT 30% OF THE TABS HAD TO BE MANUALLY OPENED, 4.) AND HERE IS THE BIGGEST BUG: iT SCRAMBLED MY BOOKMARKS !!! WHAT DO MY BOOKMARKS HAVE TO DO WITH MY TABS !!?? Beware, this extension needs a serious bug overhaul and redesign.

i should have read the reviews. loved this app on my pc. but now because of this ive lost HUNDREDS(!!!) of tabs! just look at all the other reviews. screw this app. STAY AWAY.

Turned my 100+ tabs on Android into a list of 3 tabs. The rest are lost, gone forever.

Tried to save some incognito tabs with this on Android. It closed all of my incognito tabs but only saved some of them, and even closed all of my non-incognito tabs without saving any of them!

WTF!!! I have more than 400 tabs. When I click the button, All tabs are moved to OneTab's tab. But when I click restore all in OneTab's tab, It only restore the first tab, and all other tabs are gone!

Works on Firefox for desktop, but for Android, it just closes all your tabs and leaves you with an empty page. Unfortunately, Firefox can only restore the latest 10 tabs.