Answer by Walter Rumsby for GWT - Create ListBox throw INVALID_CHARACTER_ERR Exception in IE9

The underlying cause is outlined in Invalid Character DOM Exception in IE9 - essentially IE 9 now follows the W3C DOM Level 1 standard in its implementation of document.createElement.

Previously you could create an element like this:

document.createElement('<div>');

this isn't as per the standard and now you can only pass the element name as an argument, e.g.:

document.createElement('div');

The invalid character is presumably because < (and >) are invalid character in element names.