The extension no longer stores any sessions. Its basic functionality is broken. The last update was almost 7 months ago. Has it been abandoned?

Hasn't been updated in almost 7 months and lots of outstanding bugs on their Github page. They just don't seem to care about this anymore. Look elsewhere.

I've used this addon for many years and I honestly love it, but I found an issue that unfortunately I cannot overlook at work- it doesn't save history. If you don't need your history after closing the browser, then this is a 5-star addon. Previously, I gave it three stars because I couldn't use it at work, and rarely needed it at home. I updated it to four stars because I found a workaround. If you make sure every tab is loaded, and logged in, or gracefully logged out, and set it to not auto open the latest session, you can open every website, log in, then load your last session. Your tabs will load correctly, which usually means you don't need your history.

This is the explanation I previously wrote about my issues and the lower rating: The default Firefox session manager saves the history of every tab, which is incredibly important for me, but it also leaves me between a rock and a hard place. I have to use cloud software for work. It logs you out periodically. When you sign in, it will usually resume where you were; however, when you restart your browser, it resets the session, and after you log in, it lands you on the main page. If you have your tab history, you can navigate back to the page you were on; otherwise, you're stuck with 50 (to sometimes 200) useless tabs, and a mess trying to figure out what you were doing. On the other hand, the Firefox session manager can save only one session and is incredibly inconsistent; it's a coin flip whether it will work after a crash, and the only way to guarantee a session is saved is by killing Firefox from the task manager. If you sign out of your Windows account, restart, or your OS crashes, and you forget or are unable to kill Firefox from the task manager, you're completely screwed.

I just want the pinned tabs to remain open even without restoring the session. This does nothing more than create a more bureaucratic history, just like restoring the session.

Это хорошо. Отлично. В общем радует. Все звёздочки мира ваши

It's been broken for a few months now - and nothing actually works.

It works and it works well

Unfortunately it looks like this is not maintained regularly. It caused all favicons to disappear. It took me a good 20 mins to find it out and there's no doubt it was this extension causing that. It took me another 20 minutes to report the bug with all details on github, but after 2 weeks, still no response.

The best Session Manager for FireFox

Is there a way to save into the same session instead of creating new one every time I close window? It is more intuitive and more useful.

I would give this extension 1 star, but I can't. Because this is the only one extension, which works for saving and restoring sessions for Firefox. There is no alternative.
I can't give 5 stars however, because extension is very buggy and looks like not even tested by developer properly.

Obvious issues are:
1) If you move tabs between windows - then session tracking gets screwed up Tab Session Manager cannot save this session anymore. Nothing helps. I tried disable/enable back extension. I tried remove extension from Firefox and re-install it back. Nothing helps. Moving tabs between windows is Firefox core functionality. Also its possible to move tabs between private windows. This makes it impossible to organize tabs across multiple windows when using Tab Session Manager.
2) Tab Session Manager export-import extension settings - doesn't work properly. After you import settings you notice that many options are not respected by export and do not restore back. A lot to list them all, but for sure I remember: theme, auto-save intervals, backup and other options.
3) Keyboard shortcuts for saving sessions - do not work at all. No matter which key combination, I tried everything. Only one shortcut works - open extension menu drop down.
4) Bug in intervals. If you set interval to 60 minutes - nothing gets saved every hour. I had to set to 50 minutes because of this.
5) If tracking is screwed up because any unknown reason - then it's impossible to reload extension and re-capture current session and it will always fail to save current session.

But what really works great is regular popup that asks about donations.
I would happily donate, but currently I am not aware if developer cares at all about above mentioned issues, whether those will get fixed.

Help, all my sessions saved in the last 3 years have disappeared. I hope developer notices and helps me

It seems to do most of what I expected. One part I had hoped is that it would remember window placement (where are they on screen ... and which virtual desktop are they on). Unfortunately, it doesn't do either. For me, this just seems to be another way to do what "Restore Session" already does.