FF 47 didn't install properly from a prompt. So re-installed manually OK. Only thing was No Squint add-on is not compatible and the developer says he no longer has the time to maintain it. Big shame a it worked particularly well IMHO.
The dev recommends Page Zoom which I have installed but not so good - there are others if I can be bothered to fiddle with them! To much hassle at the moment with Win10.
Tony