When privoxy blocks a small frame, notification message is displayed on white background. If a page has a non-white background this creates a white box which doesn't blend and looks ugly - check the attached screenshots with and without white background. My fix is rather brutal - I commented out the default background which is inherited by all CSSs
/*
* CSS for Privoxy CGI and script output
*
* $Id: cgi-style.css,v 1.11 2007/12/08 14:29:06 fabiankeil Exp $
*/
/*
* General rules: Font, Color, Headings, Margins, Links
*/
body,td,th { font-family: arial, helvetica, helv, sans-serif; }
#body { background-color: #ffffff; color: #000000; }
(the last line) and it works surprisingly well, other screens look good to me. Maybe you should remove this line altogether, maybe you should tweak CSSs in a finer way, but something has to be done.