There appears to be a minor bug in rxvt involving pixmaps. When a pixmap is cleared using the escape sequence "\033]20;\007", a small remnant of the previous bitmap, 5 pixels high, remains along the top and bottom edges of the window. I have confirmed this under 2 different X servers so it doesn't look like a server problem.
This is for v2.7.10 from the Cygwin distribution.
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