Bookmark All Tabs - you can get it when you right-click on a tab, or use keyboard shortcut Control+Shift+D.

Firefox now always stores the old session, and you can access it by going to the History menu and selecting "Restore Previous Session"

If you want Firefox to display the message to save the session, it can be turned back on by changing some preferences.

1. Type about:config into the location bar and press enter
2. Accept the warning message that appears, you will be taken to a list of preferences
3. Locate the preference browser.tabs.warnOnClose, if its value is set to false, double-click on it to change its value to true
4. Repeat this for these 3 preferences browser.warnOnQuit, browser.warnOnRestart and browser.showQuitWarning

If you always open the last set of tabs, an alternative approach is this:

1. Click the orange Firefox button, then select options to open the options window
2. Go to the General panel
3. Change the setting "When Firefox starts" to "Show my windows and tabs from last time"

I don't have the Orange Firefox button as shown in the demo. How do I get it. Also can I still Bookmark All Tabs as I could in 3.6?

The new interface is only default on Windows Vista and Windows 7. To get it on Windows XP you need to hide the menu bar. To do that in the View menu select Toolbars, then click on the "Menu Bar" entry.

If you need access to the menus you can press either Alt or F10 to temporarily display them.

See my first reply about accessing Bookmark All tabs

Thanks Bud, Overlooked the Bookmark All Tabs you posted in the first response. You have fixed all my problems. Much appreciated.

You're welcome

Just registered on this site to basically .. start bitchin'.

The 4.0 version is a piece of crap. I don't care if some of the features I used in previous versions are hidden somewhere or not, but "save tabs on exit" was there and it's no longer showing up. This is like going back to stone age. I agree with many who dislike the many changes in this browser, most of them remind me of MS team trying to put out a smoke screen with cute interface without any substance behind it. If you people have nothing better to do, then why screw with a v. good product? Or is this about well, ... it's free you know? Screw it. I switched back to 3.6 and will see what Mozilla decides to do with this one. So far it's nothing worth wasting time with.

Firefox now always stores the old session, and you can access it by going to the History menu and selecting "Restore Previous Session"

Just joined the site to say thanks to all who put the time and effort in solving the various problems. I have used the site many times over the years to successfully solve my problems the latest being the restore last session in firefox 4.

This .............''If you always open the last set of tabs, an alternative approach is this:

               Click the orange Firefox button, then select options to open the options window
   Go to the General panel
   Change the setting "When Firefox starts" to "Show my windows and tabs from last time"''.....................solved it for me with three clicks !

Thanks again and especially to TonyE