Steps:
1) Launch The RichTextEditor
2) Clear all the existing content
3) Type some text for ex: zzzz
4) Select the whole text and try to hit the backspace 
5) The typed text is not cleared and even you keep hitting the backspace the text is not cleared sometimes, it just stays

Launch the RichTextEditor
1) Click the find and replace button on the ribbon bar
2) Close the find and replace dialog box
3) click the find/replace button again , the form doesn't open up