I used to be able to close firefox and have all my opened tabs saved. When I open firefox again, those tabs will be opened as I last closed firefox. Now, I am not able to do it. The firefox was crashed at one time earlier and I have to open the task manager to force it to close because it is frozen and so was my computer. After I opened it again, there is no tabs saved which I kinda expected. Then I go on web surfing and browse various websites. Now, when I close firefox, a box pops up warning me about the opened tabs will be closed. So I googled the symptom and it brought me to this website, telling me that if I set "tools->open->general->When firefox starts" to "Show my windows and tabs from last time", it should behave as it was before. I tried that but it doesn't work. Any help is appreciated.