This isn't so much as a crash exactly, but certainly as frustrating. I generally operate with a minimum of 5 tabs open within 1 FF window (Windows 7 64-bit) and this window is normally maximized. Since FF 5, I have noticed that as I click from tab to another tab, the tab will jump out unexpectedly into a new window. I'm an experienced computer user so this is not a mistake of the mouse or my hand. I also can't quite pinpoint what exactly is happening but it's definitely upon clicking as I can Ctrl+Tab through the tabs normally. It's almost as though there is a delay when you click on one tab, then when move the mouse to the next one it thinks you're dragging the tab away from the window. Hope this makes sense. I have just upgraded today to 6.0.2 and it is still occuring. Any help on the matter would be gratefully received, I use FF as my development tool with Firebug, but got to say this infuriating at times.. Cheers Chris