It doesn’t look like a very satisfactory resolution was found, even though it’s marked “resolved”.
I’m getting this, both before I just upgraded to 2.0.3 and afterward. At some point the WYSIWYG editor just stopped working, but I don’t recall anything extraordinary.
At any rate, a simple grep shows that this message is generated on line 5851 of wp-includes/js/tinymce/tiny_mce.js . It looks like two lines earlier:
var templateFunction = tinyMCE._getThemeFunction(‘_getEditorTemplate’);
isn’t returning anything useful so it’s displaying the message. I’m not that handy with JavaScript but I’ll poke around to see what I can find.