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.

used to work but recently after the notorious Firefox update it's now broken and author does not respond.

After several months of using I can say: Absolutely Vital. When you don't want to close a window (just in case you possibly would miss the tabs), save the window instead. No more gazillions of windows, and no tab is lost.

works

Very good. Just wish there was an option to remove duplicates.