You mean they combined something else into FF that is now causing it to be much worse than 2 ever was? Because that was never a problem with 2. Memory use would not increase while idle, only while actively browsing from tab to tab, opening new ones, closing others, etc. Even then, it would take weeks to get really bad. Right now, 3 is up to 300 MB in just 1 day of very little activity. I'll be closing it here shortly.