Restore Mozilla Firefox tabs after a crash on Windows
Mozilla Firefox has the option to open tabs from your previous session.
Options->General->Startup->When Firefox starts: Show my windows and tabs from last time
But sometimes things go wrong. If your browser starts without showing your previously open tabs, you can restore the session under your History menu.
History->Restore Previous Session
If that option is unavailable and you've experienced a serious crash, you can still recover your old tabs if you have Windows System Restore enabled. Paste the following path into a Windows Explorer window:
Enter the resulting profile folder and locate the file called sessionstore.js. Right-click on the file and choose "Properties" from the contextual menu. Select the "Previous Versions" tab and restore to a date when Firefox remembered all your tabs.
When you reopen Firefox, you should see all your previous tabs.