Line disappear after context menu

[Garry Yao]

Environment

IE8 Quirks

Reproducing Procedures

1. Open any of the sample page;
2. Load the document with the following content and selection:

   <p>
   	line1</p>
   <p>line2<br />
   ^line3</p>
   

3. Right click on the marked position to open context menu;
   • Actual Result: The third line keep disappearing from the screen until the context menu is closed.

[Jakub Ś]

Issue is no longer reproducible. I have checked it in latest CKE 3.6.3.