Firefox 3 is great overall, even (especially) the Awesome Bar, but there is one annoyance. If you accidentally untick “Do not ask next time” when closing Firefox with multiple tabs open (e.g. by clicking anywhere above the buttons you do want – an easy mistake), it won’t ask you to “Save and Quit” again. The ability to Save and Quit is one of the great new things Firefox 3 has introduced.
Fortunately, you can recover. But only if you know what has happened and what to do.
Tools>Options>Main>Startup>When Firefox starts – Set to Home Page
Make sure Tools>Options>Main>Startup>Tabs Warn me when closing multiple tabs – TICK