If you've been defiantly clinging onto Firefox 3.6 by your fingertips, bad news. Mozilla is officially putting it to sleep -- whether you like it or not -- by auto-updating users to version 12. You've still got a few days to bid your emotional farewells, with the switchover being pegged as early May. But, the browser's creators stop short of setting a date for you to get the flowers delivered by. Official support for the 2010 release finished this week, and the final bout of security fixes was back in January. At the other end of the spectrum, Firefox