No, I can't.
The problem is not simple and a simple page won't demonstrate it. Our apps are very complex.
We've determined that there are 2 areas where the problem arises.
The first is that the window seems to get the focus when an opening value is assigned to the Text property of the editor in server-side code.
Please check your code and determine if you are setting focus on the window when the opening value of Text is not blank.
We've also determined that setting EditCompleteDocument to true may have some effect on how focus is being set. You should review that code as well.
Let me know if you locate the problem.