Surprisingly intuitive and does everything I expected it to. Kudos.

No export for sessions though it says you can export. The most telling is there is no importing of sessions anyways. Backup does not work. I gave the full file path to the back up folder then restarted the browser and found nothing. Exporting your settings is the only one that works. The ability is to sync doesn't seem there either. "Sync auto save sessions" being checked by default doesn't seem to sync anything. "Enable Cloud Sync" is appended with "(Beta)". So there doesn't seem to be a way to reliably store your sessions to use them between devices using Firefox. Google Drive stores general files so I don't understand how Google Drive can be used to sync sessions between devices and browsers running the same extension. I use Firefox Nightly. There is also no way to simply add a tab to a session which may be on another window. You must copy and paste the URL to the window you want, then rewrite the session to group that tab with the ones you want. Overall, it is good, but unless if you are only using one browser on one device, the ability to backup, export, and sync really lowers the score for me.

Cloud sync and tab restoration
beautiful

I like a lot this plugin, but its such a shame that I can't Sync the session using my Google account. When I click the Cloud Sync this says "Syncing..." but never syncs. I will wait anxious for this feature

Great extension.

I'd give it 5 stars if only it has RENAME capability on the Session & Link names, as well as DRAG 'N DROP capability of those sessions and links . Please refer to a Firefox extension named 'Session Sync' for reference.

複数のタブやウィンドウを保存しておく機能が気に入っている。Android版Firefox Nightlyで使えるようにしてほしい（indexedDBが使えないとエラーが表示される）

doesnt work automatically session saving!

really nice extension, will use it. If I only could put my sessions into "folders" to hide my private things - that would be 5 stars!

Simply an amazing tool to save your day!

I had over 75 GB of backup files in the downloads folder because I mistakenly turned off Reminder. You see, I have to manually delete old backups, even though a session manager should manage it, and it is possible through WebExtension API which Allow unlimited storage. I am sorry to say but I am disabling it, until a better solution is available :(

Tab Session Manager basically saves copy of your windows or groups of windows whenever you close them, or on demand, for you to summon back whenever you need them. It's a really great add-on for people with tons of tabs and windows! The interface is a bit aggressive with its popup asking for donations, but it's fine otherwise!

My only request is that I'd massively prefer a sync option with my Firefox account over the provided Google drive option. In corporate environments, it's not always an option to use Google services! Changing this would get my review up to five stars.

This is one of those essential addons that you just must have, no questions asked. I configured it to auto-save the tabs every 30 minutes. It has already saved me a lot of time and headaches when I experience crashes, and the browser can't always recover the last session by itself.
Thank you Sienori!