<!DOCTYPE HTML> <html> <head> <title>Resize Reflow Test</title> </head> <body> <div style="-moz-column-width: 12em; border: silver solid; width: 30em" id="outer"> x <div style="border: dotted; background: aqua; color: gray;"> blah<br> blah<br> blah<br> blah </div> </div> <script> document.body.offsetWidth; n = document.getElementById("outer").firstChild; n.data = ' '; </script> </body> </html>