Steps to reproduce...
- Launch the SE sample with the SDI Code Editor and the default selection of the C# language (all defaults here)
- Click inside SE and type CTRL+A to select all the text
- Type DEL to clear the document
- Now type some text on the first (and only) line and hit RETURN
- For some reason... SE scrolls down and hides that first line for no obvious reason since there is plenty of room to show the entire document.