<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> <html lang="en-US"> <head> <title>reftest, bug 424236</title> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <meta http-equiv="Content-Style-Type" content="text/css"> <style type="text/css"> body > span { outline: 1px dotted black; } /* can't compare to border combined with negative margin because of margin collapsing */ body > div { display: block; outline: 1px dotted black; } </style> </head> <body> <span>A</span><div>B</div><span>C</span> </body> </html>