Make sure that you do not run Firefox in permanent Private Browsing mode.

• https://support.mozilla.com/kb/Private+Browsing
• You enter Private Browsing mode if you select: Tools > Options > Privacy > History: Firefox will: "Never Remember History"
• To see all History and Cookie settings, choose: Tools > Options > Privacy, choose the setting Firefox will: Use custom settings for history
• Deselect: [ ] "Permanent Private Browsing mode"

Thanks for the reply! Unfortunately, that's not the problem, as I have it set to remember history. Thanks again

Firefox 4 and later versions save the previous session automatically, so there is no longer need for the dialog asking if you want to save the current session.
Use "File > Exit" or "Firefox > Exit" (Mac: "Firefox > Quit Firefox") if you want to restore multiple windows.
You can use "History > Restore Previous Session" to get the previous session at any time.
You may need to click the orange/gray Firefox button to see History.
There is also a "Restore Previous Session" button on the default about:home Home page.

Another possibility is to use:

• Firefox/Tools > Options > General > Startup: "When Firefox Starts": "Show my windows and tabs from last time"

Thanks for the reply, I think all of us do not struggle with restoring our sessions, which now happens automatically as you correctly point out. The issue rather is that this AUTOMATIC behavior is not always wanted: I would rather have Firefox ask me upon quitting if indeed I wish the session to be restored the next time so that I may choose "NO" (and start with a blank session next time) or "YES" depending on the situation at hand. Until FF 6.0.1 the browser.showQuitWarning boolean did the job, but now seems to be ignored.

Beyond the asking if I want to save my tabs, I find the warning box to be highly useful when I accidentally hit Command + Q on my mac.. when I was intending to hit Command + W (which is right next to Q) or Command + Tab (also next to Q). I liked that if I accidentally hit the Q, it would ask me before quitting.

I recently came across this method to change that command to Shift+Ctrl+Q.

• [/questions/783393]

• http://www.mactipper.com/2008/03/add-keyboard-shortcuts-for-applications.html

defaults write NSGlobalDomain NSUserKeyEquivalents '{"Quit Firefox" = "@$Q";}'

Don't forget the "browser.warnOnQuit" setting.

I also had this problem. Check your 'Startup' setting in Options > General. If it is set to "Show my windows and tabs from last time", then toggling the 'warning' settings won't make a difference.

Set it to "Show my home page" and you'll get the familiar message again.