Latest version of Firefox is 4.x which is super fast and comes with many features that no other browser can beat it. (Previously we wrote review of Firefox 4, if you interested you can read it as well.)
After upgrading from 3.6 to the latest stable 4.x version when you close the browser inadvertently and again restart all your previously opened tabs or pages, they just goes away and the Firefox opens the default homepage. This may seem to be a problematic feature to novice users with this new version of Firefox.
One of the available option to restore the Pages which were lost with the new session. In order to perform this you need to type about:sessionrestore in your Firefox™s address bar:
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This will throw you a nice information window in Firefox 4 saying:
Well, this is embarrassing.
Firefox is having trouble recovering your windows and tabs. This is usually caused by a recently opened web page.
You can try:
- Removing one or more tabs that you think may be causing the problem
- Starting an entirely new browsing session
Like this:

Just click and select the Window you want to restore (or you can select the whole session) and click on Restore button just like the above screenshot to open all the closed tabs.
Firefox 4 is great, is not it?
What if we have already opened some windows and then we want to open the tabs we had before ?
Or go to History>Restore Previous Session, a lot easier and faster