I am getting error only in IE7 as document.body is null; when I debug with Microsoft script editor I am getting the error in the following line:
i.e.
You can appendChild to document.body but not if the document hasn't been loaded. So you should
put everything in:
window.onload=function(){
//your code
}
This works or you can make appendChild to be dependent on something else like another event for eg.
https://www.w3schools.com/jsref/tryit.asp?filename=tryjsref_doc_body_append
As a matter of fact you can try changing the innerHTML of the document.body it works...!