how to remove p or br in empty field ?

The content of the apparently empty field (when the page loads) varies according to which browser you use.
From my brief tests, for IE under Windows the field is truly blank (about 91% of my users)
With Firefox under Windows or OS X, you get <br type="_moz" />
In Safari under OS X, you get &ndsp;
Under Opera 9.24, it doesn't load properly, so I can't click the 'Source' button to see what's there.

All this means that its not possible (or rather, its not easy) to use JavaScript to reliably test if the field is empty, since for some browsers, it never is:

var oEditor = FCKeditorAPI.GetInstance('theBody');
var theBodyTest = oEditor.GetXHTML(true);
if (theBodyTest.length==0) {
  alert('You need to enter something for the body of your story.');
  return false;
}

How can we fix this, please?

Chris.