IE and Vista ends January 2016, so I need Norton 360 to work with Firefox

Norton Password Manager
1

I understand that from 16 January 2016 I will not be able to use Internet Explorer (I use the compatible version 9 now) as my operating system is Vista.

So I will need another Internet Browser.

I used to use Firefox until last month when I realised that Norton 360 was not compatible - I'd been exposed for c 2 months!! AND Norton had not let me know!

So what should I do? I gather Norton is still not fully compatible with Firefox 41 and 42.

Thanks