Problem updating ICSharpCode.Texteditor

I had the following problem when setting text to the "ICSharpCode.Texteditor" control.

texteditor.Text = s;

The text was set, however the old text was still visible:

As you can see the control is not updated, when the text is set. The old content is still visible. After I scroll, the control is updated. The solution is to update the editor:

 texteditor.Document.RequestUpdate(new TextAreaUpdate(TextAreaUpdateType.WholeTextArea));
 texteditor.Document.CommitUpdate();

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