OneTab certainly does a Fine Job!

This is perfect and amazing and full of useful features, like moving all the tabs into one firefox tab or window, even pinning it, and grouping the tabs in that window, naming them, locking them so that when you open the link you won't lose the tab in OneTab, EVEN being able to share all your tab links or a subgroup of your tabs to your frined via a generated link! just by installing OneTab and managing your tabs you can have a new firefox! It feels great to use it, DONT MISS IT.

missing date at frequently

EDITED: All my tabs are still there, the addon is perfectly working for me. But it seems it's not the case for most of the users here. I don't know why it's working for me, and not for other users. I suggest you to use another addon, that seems better now: better-onetab instead. Because Onetabe hasn't been updated since 2017, it really seems it's not maintained anymore!

My previous review: It doesn't lose your tab, and if you want to be sure it'll never lose any tabs, the extension lets you save them to the disk in a html format, very handy.
This is the extension I use to keep my sessions, close in one click the tabs when I have many many, and save them. One of the best memory saver.

I lost all my tabs when restoring them from the page.

Only after a while I realized how helpful this add-on is! I am using it now all the time.

OneTab lost all my tab data many times. I thought that maybe automatic upgrades/updates on Firefox may have been the culprit, but having just reinstalled it for the first time in a while, it immediate lost many windows of data for me, IMMEDIATELY after clicking on bring all windows into One Tab. Thanks, One Tab.