[Vinnl]

I'm not sure whether it fulfils what you're looking for, but Mozilla just ran an extensions challenge, and one of the winners was Session Sync.

[0] https://extensionschallenge.com/ [1] https://addons.mozilla.org/en-US/firefox/addon/session-sync/

[newscracker]

Thanks, I did see the Session Sync extension before (and again now after the challenge winners were announced). Unfortunately, it seems to be quite thin on features, with the man advantage being syncing the sessions easily since they're stored as bookmarks. I also found the UI unintuitive (for example, I have to click on the extension icon, then go to the history tab, and then click on the current session to see the Save button).

Tab Session Manager is comparatively a lot richer in features, and also allows importing from the (legacy) SessionManager sessions.