Whoa! Now it doesn't work anymore.
That solution worked, and now it doesn't. Sessions that are saved just continue to pile up; if I edit the prefs.js file manually it gets
overwritten with the same old information I deleted, next time I run Firefox...
Cannot get rid of the old sessions via about:config in the browser, either (as a user reported he was able to, in a post elsewhere).
I even removed firefox and the settings for it in ~/.mozilla/firefox, and reinstalled from a fresh download, and it STILL has all the session saver stuff.
I installed an "extensions uninstaller" extension (yes, there is such a thing) and it was unable to UNINSTALL session saver.
At this point I'm sorry I ever installed the session saver! If it worked right, I would like it. But it doesn't, and apparently there's no way to get rid of it.
Anybody got any ideas?