What I do is that I have changed the default color of Windows window background (the item is literally called "Window" on Win7, see the link below). If I remember correctly, UR just accepted this as the default item background color.
Works very nicely for me. I have most of the text related apps with my favorite sepia-like color background.
Custom colors were very easily achieved up to Windows 7 (for example see here:
http://www.bbc.co.uk/accessibility/g...n7/index.shtml). Sadly, you'll need to find other ways to do that in the downgrade called Windows 10.
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