On IE9 if you select some formatted text and click on "Remove Formatting" this works OK. But if you immediately click on "Undo" then only a portion of all the text in the editor survives. I think it is only the current "line" of text.
This seems to work fine in IE9 Compatibilty Mode, IE8, IE7, Firefox, Safari and Chrome.
This seems to work fine in IE9 Compatibilty Mode, IE8, IE7, Firefox, Safari and Chrome.