Very nice

Disculpen, pero seria bueno poder ordenar los enlaces cuando estan en el onetab y poder marcar aquellos a los cuales uno cliquea para abrirlos en una nueva pestaña del Firefox

Monochromatic icon for dark and light themes are needed. Please some automatic backup should be there.

Why does Mozilla insist on keeping its pages as bright as the sun?
Please don't follow in their footsteps. This is a great extension but the white background is killing me here.

I'll (without hesitation) give this extension a 5-star rating since it makes the Firefox UX that much better, but give us some sort of dark background!

A very nice and useful addon, but that white kills the eyes. Please add a simple color chooser for both foreground and background, please.

Information about container is not stored. Tabs aren't restored in container tab like work/media/shopping/…
Missing search/filter input box.

Sehr praktisch! Nur schade dass man die Hintergrundfarbe nicht dunkel wählen kann!

Hasznos

A must have addon for tabaholics like myself.

There's only 3 things missing in my opinion:
* The ability to merge 2 windows sent to OneTab
* The ability to undo removing a tab inside OneTab
* Firefox (but not any Chrome based browser) always unpins the pinned OneTab on browser restart.

Helps me to clean the unused tabs safely. However, the toolbar button is very easy to misclick. Perhaps it should ask for confirmation or open an action menu?

OneTab is essential. However, as of Sep. 2020, it has a new bug: it disappears after the browser is launched, and you have to disable and re-enable to make it work. They need to fix this. Also, the developer could make it so much better, for example by allowing more ways to manage and display the tab list.

Broken OneTab? Add-ons Manager -> OneTab -> Toggling "Run in Private Windows" every time Firefox starts-up seems to re-enable the OneTab extension.

My biggest gripe with OneTab is the insistence of utilizing: "https://www.google.com/s2/favicons?domain=" rather than other options or even no favicon. Yes, I would prefer an option to not even waste resources on the favicons.

It broke on the recent Sept 2020 update, but following a suggestion to turn it off and on again under about:addons page actually fixed it. I've been using this for a few years and continue to love it despite this.

Great Addon, just lacking a dark mode. Please add it & save me from going blind at night xD

OneTab's icon keeps disappearing every time after browser restart.... I think it has started recently.... It is there, but transparent, or without an icon, then I have to go into Extensions - Disable - Enable again, then I have the icon, next time it is disappeared again...

Overall it's a good extension but I've had trouble getting my tabs back twice now. This ext would get 5 stars if there was the option to export automatically. As a developer, I don't see why this would be a difficult feature to add. After the first time, I started exporting my tabs periodically so if I did lose any then I probably could remember the most important links from recent memory. This time I lost all my tabs and the icon disappeared. From reading the reviews, I'm far from alone.

To restore my tabs I found a review with instructions. Go to ~/.mozilla/firefox/2tz4pwhp.default/extensions or a similar path in the Files GUI then double-click on a file called extension@one-tab.com.xpi . This opened up onetab, restored my lost tabs, and fixed the missing icon in my browser after giving permissions in the oneTab pop up in my browser and refreshing my OneTab open tab. I am using Ubuntu 18.04 LTS and Firefox 80.0.1 (64 bit). Hope this helps.

Update: This only fixed the problem temporarily. I had to follow the steps again after restarting my computer. An easier step, as was already mentioned in some reviews, is to simply go to Add-Ons in Open Menu (top right corner) and then disable OneTab by clicking the white circle in the blue oval. Click it again to enable OneTab and it should be working again.

Re-evaluating my review. The developers have been in contact and seem to have fixed the issue.
There might be a need for a automatic backup feature that makes a backup every week or perhaps prior to an update occurring in case something goes wrong. Many users lost very important info and I can't imagine what it was like for them!