This issue seem to occur only on Firefox:
I've got an error saying "getBoundingClientRect is not a function" on a valid dom element included in the page:
var flashElement = document.getElementById("flash_2ffe3a7c");
result:
<object type="application/x-shockwave-flash" id="flash_2ffe3a7c" name="flash_2ffe3a7c" data="http://www.url.com/myfile.swf" wmode="transparent" style="top: 0px; left: 0px; z-index: 4102; position: absolute; width: 399px; height: 6px;" width="399" height="6">
flashElement.nodeType is 1
flashElement.nodeName is OBJECT
but
flashElement.getBoundingClientRect is undefined.
whereas
flashElement.getClientRects is a function.
Is there a known reason why getBoundingClientRect is undefined?