By using this method the font information is lost when the Rich Text Items reside in different documents and use different fonts.
The result is, that the content of the new Rich Text Item gets the first divergent font (other than standard).
If this divergent font is a special font (i.e. Wingdings), the complete text is unreadable.
I expect the method AppendRTItem to append the Rich Text content to an existing Rich Text Item and also preserve the font information of both Rich Text contents (like copy / paste in UI).