<!DOCTYPE html> <html> <head> <script> function expStr(s, n) { for (var i = 0; i < n; ++i) s += s; return s; } function boom() { var s = document.getElementById("s") var t = document.createTextNode(expStr("x ", 15)); s.appendChild(t); document.documentElement.offsetHeight; s.removeChild(t); } </script> </head> <body onload="boom();"><div style="width: 1px"><span id="s"></span></div></body> </html>