The problem occurs in specific situations when a list depends on a style that hasn't been added to the fragment in the clipboard yet. Workaround: Replace the fragment in the clipboard with one that is already "fixed", as in the attached MainWindow.cs.txt
The item is declined as duplicate of https://feedback.telerik.com/Project/143/Feedback/Details/200218-richtextbox-text-copied-from-ms-word-and-containing-lists-linked-with-styles-can . Use the new item to vote and follow for status changes.