So I think I have a large stuck pixel on the screen of my Macbook - a bright white dot. Except - shouldn't it be most visible if something dark is being displayed around it? By contrast, it's most visible over a white background, and can almost be 'covered up' by putting something black over it. Is it a stuck pixel or something else (in which case I'll stop having PixelFixer running in Dashboard whenever I open it up)