Since upgrading to the latest TineMCE will not fix that,I have quick troubleshooting note for this problem and though is not a “real” fix it’ll make your life easier while editing you WordPress site… at least you’ll see what you are editing :D!
In Firefox go to Preferences>Content> and click on the Advanced button on the same line as “Enble JavaScript” once the next configuration area “Allow scripts to will show up uncheck the “move or resize exisisting windows” and that should do it. I also unchecked “raise or lower windows” because those are mostly used for ad pop-ups 🙂
Good luck with this one!
