I have IE9 and use WordPress 3.5. I got a notice for one of my sites that I had an update to my editor. I did the update, and it said it was done successfully. But now when I try to edit any of my pages or posts, none of my content is there and there is no tool bar.
I also have another site that is using Dean's FCKEditor For WordPress 3.3.1. This editor works fine, and I have never recieved a notice saying there are any updates to it.
I have tried to re-install Dean's FCKEditor 3.3.1, but it doesn't install anymore