Type something in plain text in the editor (or example when posting in a forum), press ctrl+I to turn on Italic. Nothing happens. The Italic button is still unselected. Start typing and italic text is produced and now the button switches to its "pressed" state.

This gives the impression that turning on italics has not worked. Also, you cannot look at the editor and know what will happen when you start typing. You have to type and only then do you discover whether or not Italics is on.

This same behaviour happens with bold. Not sure what else.