When I go to close FF it would ask me to save all the tabs or delete etc. Now its not giving me that option. It says close tabs or cancel. How can I get that first option back?

first open new browser window and write "about:config" to address bar.After press enter, there is WARNING but dont worry we ll change only one thing. Use filter and write to filter "browser.showQuitWarning". You ll see three parts" user defined, boolean and false". Go to false option and press right mouse button and change it to true. Then close browser and open again. Now you have save option. I translated this from "http://www.doancan.com/firefox-4te-sekmeleri-kapatirken-kaydet-uyarisini-acma.html". Also there are pictures in here.