Browser page rising and filling screen..

Hi All;

Hopefully, I am posting this in the correct place

I have been using windows 8 for the past 2 months now ( hate it )., as of a short while ago, I am finding that if I have a few browser pages open (using Firefox) that each page is rising and filling the screen, meaning I have to move the mouse to the top of the screen to see my other browser pages open, its very annoying and I cannot find how to stop this happening

Not sure if its a Firefox issue or a windows 8 issue

I only have basic knowledge of PC's so any help or advice would be appreciated

Thanks