window.opener.document.getElementById not working

[MaxiWheat]

Hi,

I am trying to get my values entered in a popup window to populate the
fields in the opener window. Actually when I do something like this :

window.opener.document.getElementById('myElement').value =
document.getElementById('myOtherElement').value

it works in IE6, but why FF does not support
window.opener.document.getElementById ? When I inspect the DOM with
Firebug, I see that the method getElementById does not exists for
window.opener.document ...

Anyone knows an alternative that is not obsolete code and works for IE
and FF ?

Thank you

[joe...@googlemail.com]

I had a recent problem involving getElementByID:

IE and Opera were both retrieving the object via
window.opener.document.getElementById, but Firefox wasn't. Problem
turned out to be with the form itself, the form field I was trying to
access - a select - didn't have an id tag, just a name. IE and opera
were ignoring this and using the elements name, whereas FF was
returning NULL untill I added the id tag.