I couldn't get webkit to render a frame with no borders and no margin in WebKit, so I assumed I was doing something wrong, and went looking for some online reference. I found a [frames tutorial][1] that explained how a web designer should get around this problem: > You can get rid of the borders if you like. Officially, > you do this using frameborder="0". I say, officially > because this is what the HTML specification specifies. > Having said that, different browsers support different > attributes, so for maximum browser support, use the > frameborder, border, and framespacing attributes. [1]: http://www.quackit.com/html/tutorial/html_frames.cfm Unfortunately, even setting all of these leaves an unsightly white margin in WebKit (though not in Gecko). The tutorial's minimal test case is [here](http://www.quackit.com/html/tutorial/frame_example_frameset_3.html). Interestingly, setting a 1 pixel border eliminates this margin.
The sample page appears to work properly now.