I am having the same issue with my visual editor.
*Using IE9 doesn’t cause the issue
*Using Firefox 4 causes the issue
*disabling Multipage Toolkit fixes the issue
*Using IE9 doesn’t let the visual editor go full screen causes headace for writers
Now if i disable Multipage Toolkit Plugin which would fix the issue but it would break the site as all feature article have more than one page and this is not good at all. I also found out that the plugin hasn’t been developed on since 2008 which is real worry.
I really need it fixed ??