I had been using it for a long time without issues, it saved me 2-3 times; but yesterday my computer crashed. My waterfox session file must have been corrupted and it restored it from the recovery one (previous.json) that is somehow 2 months old (thank you mozilla for not updating it more frequently). I immediately went to tab session manager to restore; but surprise surprise, all the backups are gone. At some point it seems the automatic backup feature stopped working and somehow even the older sessions disappeared. Idk if it was a browser update, error or that they were older than X and automatically deleted.
TLDR, even having this extension enabled to prevent the loss of my session, I still lost my session. I will either look for an alternative extension and/or start backuping the session file manually.

Would be nice to be able to save Tab Groups also.

all tabs re-opened, but tab groups are destroyed

Did not save my fucking tabs.

20250607 It does the job as it should! No complaint, till today that it double saves my open tabs. For example, if i have 2 windows and 50 tabs on each, it saves and opens 4x windows and 200 tabs. I use this extension for a long time now (years), without complaint. I don't know if it's firefox's fault or the extension (probably a firefox thing). Please take a look at this Sienori, thank you!

### 20250608 EDIT: I don't know what happened yesterday, but today it seems to be working fine as always, as it should, so i came back to edit the review, because, again, you've done an Awesome work sienori! You 've saved us many hours from being lost! Thanks, and please keep it up!! :-)

I tried Tab Manager Plus but found it USELESS. It doesnt save sessions like it says it does but this one I installed and BOOM, So easy to click on it and choose save session, thank you!

Destroying my tab groups every launch. All Tab Groups need to be recreated, all tabs need to be readded to their groups. Disabled until this is supported.

The only problem that I have with TSM is that it does not play nicely with Simple Tab Groups at the moment. I use STG all the time, so unfortunately until this bug is sorted, TSM is a non-starter for me. Which is unfortunate because it is highly recommended and I would like to use it. (P.S.: I run a Mac using Monterey so quite old, nevertheless, this post is accurate as at 2025-05-08.)

Works really well. I would like functionality to name windows and have that title persisting after saving and restoring a window or session. I'm using extension Window Titler that prefixes the name of the window with [MyTitle], followed by the name of whatever tab is currently open (so window title changes dynamically). That functionality is perfect, but that title is obviously lost when window is saved.

This is an excellent and convenient extension that I've used for years. It has saved me many times when I would have otherwise lost all my tabs. I love that I can create manual and automatic saved sessions and even back up to the cloud or export to a local file.

If possible, I would really love the ability to backup up tab groups. I know that it is a really new feature and I don't know if extensions have the ability to do that, but it would be very helpful.

I think that it would also be nice to have a feature to pin some sessions to the top of the list to make them easily accessible.

This extension is almost but not exactly quite what I am looking for. I really really dig the idea but the way that sessions work essentially just makes this a more complicated history tab. I would like the option to update and overwrite an auto save instead of creating a whole new save. With autosave a new save is created that overwhelms manually created sessions. I would expect the behavior that each window is an independent save and duplicates are not created. Additionally with events such as window and browser closing, the save feature creates multiple identical and redundant sessions.

Not restoring previous.jsonlz4

Tab Session Manager has been working largely without problems for years.
However, since April 6, automatic saving is no longer carried out, neither automatic saving, nor regularly saving the session, nor saving the session when the browser or window is closed.
There are approx. 1800 open tabs

On two different ff versions 91.9.1 and 115.20 it randomly deleted ALL sessions, on one ff i lost a sessionwith 2000 tabs and on the other 1800 tabs, backup is disabled by default, no other backups are kept and recovery is possible only if you have all your history from the past 6 months. evrything else is pretty good.