TSGL: Closing Firefox Tabs

[Mike Ferrell]

I have a problem that just started recently with Firefox.  If I have more than one website open and click on the X to close it Firefox closes up everything and shuts down, even though I have the option checked to remind me that I am closing more than one tab.  In fact, previously each tab would show up on the tab bar and I could click on one to close it without closing all the others.  Now, only one shows up on the left side, even when I open several, as if the latest one is open "on top" of the others.  But if I click on the X on the left side to to close that tab, it closes, but then I have an empty white page with "unknown" as the name of the site.  The others that I had open are nowhere to be found.  What's up?  And how do I get back to showing all tabs across the tab bar so I can close only one if I want?  I have played around with the Tools>Options>Tabs until I'm blue in the face!
Mike