UserAgent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:51.0) Gecko/20100101 Firefox/51.0

Steps to reproduce the problem:
1. call up any website
2. 
3. 

What is the expected behavior?
normal colours (checked with other browsers ie firefox where colour rendering is normal)

What went wrong?
all colours in content windows are greyed /dull / dark

Did this work before? Yes this morning 19.02.2017 til 12 AM GMT

Chrome version: <Copy from: 'about:version'>  Channel: n/a
OS Version: 10.0
Flash Version: Shockwave Flash 24.0 r0