When I first downloaded FF 4 on my netbook I got the first run, welcome to FF 4 screen. As usual. But it keeps coming back. Every time I open FF it opens the welcome screen in the first tab and in the second tab is my home screen. If FF is already open and I want to open my home screen in another tab, it simultaneously the welcome screen in one tab and my home screen in another. I will not upgrade the rest of my machines to either FF4 or 5 until this is fixed.