[IE] In a pre tag, after hitting enter, the caret does not show up in a new line

[Sa'ar Zac Elias]

To reproduce

[IE]

• Open the demo and switch to source mode.
• Insert the following content and place the caret as marked:

  <div><pre>Text^</pre></div>
  

• Hit 'Enter'.

Notice that the caret is going back to the stat of the line.

• Write some text.

Notice that the text is written in a new line.

[Jakub Ś]

Reproducible in previous versions of CKE. Works fine under latest stable (3.6.1).