On Firefox 3.6 I had it set so that when the browser would launch, it would display my homepage; the “Show my homepage” option. If I had multiple tabs open and I had to close the browser, I would get the Do you want Firefox to save your tabs for the next time it starts? message and I would select Save and Quit. This way the next time I opened Firefox I would be presented with my tabs from the previous session.

Sure, I could have set it so that when Firefox launches it displays my tabs and windows from last time; the Show my tabs and windows from last time option. But I don’t always want to see my last tabs when I launch Firefox. It’s only sometimes that I have to close the browser but want to save the tabs for the next time.

After upgrading to the final version of Firefox 4 (did this as soon as it was rolled out ), I noticed that I would not get the Do you want Firefox to save your tabs for the next time it starts? message anymore. Checked the Settings and nothing changed. The Show my homepage option was selected and the Warn me when closing multiple tabs option was selected as well.

Then I found out it is an about:com problem. To solve it I had to:
- Type in about: com in the address bar -> click I’ll be careful, I Promise!
- Type quit in the Filter text box. Noticed that browser.showQuitWarning was set to false. Aha, that’s why Firefox wouldn’t ask to save my tabs.
- Double click browser.showQuitWarning so it’s value changed to true.
- Closed about:config.

Now when I have multiple tabs open, I once again see the “Show my tabs and windows from last time” option.