Posting in the Magento forums has been disabled pending the implementation of a new and improved forum solution which should better serve the community.
For new questions please post at magento.stackexchange.com, the community-run support site for the Magento community. We will be providing updates on the new forum solution soon. For questions or concerns please email email@example.com.
I just fixed a similar issue. The instructions within tinymce are to change the document.domain value in tiny_mce_popup.js. However this doesn’t do anything because the problem is that tiny_mce_popup.js cannot be accessed or executed.
Instead add this to the top of the tiny_mce.js file:
document.domain = ‘yourdomain.com’; // no need to add www, etc.