Been ages since I've tried FF. Downloaded it, opened BBC, lag and stutter when scrolling the page. Uninstalled, it's just awful to use when Chrome is pretty smooth.
Something wrong there - I load the BBC landing site or news page in like 1.9 seconds (though some images stream in as I scroll) and it scrolls up and down perfectly smooth - might be related to your GPU power management and/or hardware acceleration settings. Same on my phone - FF scrolls BBC site fine.