When I started using the beta version of Firefox 3, I quickly discovered a bug (which remains in RC1): Even though I had enabled the "Warn me when closing multiple tabs" option (Preferences -> Tabs), Firefox did not give me any warning when I accidentally pressed Cmd+Q. It would just quit without a prompting me, even if I had 15 tabs open!
In Firefox 2, enabling "Warn me when closing multiple tabs" option would cause this prompt to appear whenever I pressed Cmd+Q:
I searched [email protected] for an open bug regarding this problem and quickly found Bug 422040 - Quit Firefox 3 beta 4 does not give "closing multiple tabs" warning. I commented about my own experience regarding this bug and further confirmed its existence in Firefox 3 RC1.
Finally, Paul O'Shannessy explained in comment #24 how the warn on close functionality works in Firefox 3:
Do you have the start up behavior to restore tabs & windows from last time?
If so, when you quit (cmd-Q) the dialog regarding save session will not show
and Firefox will quit. Session will be restored upon starting Firefox.
This used to bug me until I thought about it more. Perhaps a dialog confirming
that you intended to quit is in store for this case, but that would be a
different bug. On the plus side, if you hit cmd-Q by accident your session
So basically, if you want to be warned when closing multiple tabs in Firefox 3, you need to make sure your "When Firefox starts" option (Preferences -> Main) is set to "Show my home page" and not "Show my windows and tabs from last time". Setting it to the latter prevents the warning dialog when using Cmd+Q (however, you will get the warning if you try to close Firefox by pressing the X icon with your mouse).
To further confuse things, the warning dialog that comes up has a "Save and Quit" button. This button saves and restores your tabs the next time Firefox starts, which overrides your "When Firefox starts" setting of "Show my home page".
Talk about inconsistent behavior. Even though this bug seems to be limited to Mac OS X, I really hope it gets fixed in the final release. But if it doesn't get fixed, I'm glad it's at least possible to get the warning dialog when pressing Cmd+Q and that you can choose to "Save and Quit", even if it means making silly changes to the "When Firefox starts" option.
One of the commenters mentioned the following workaround. I tested it with Firefox 3.5.7 on OS X 10.6.2 and it works perfectly:
- Install the Session Manager Plugin
- After restarting firefox, Go to Tools > Addons > Session Manager > Preferences
- Under General, set “At Shutdown” to "Ask whether to back up the current session"