The methods of the document editor you are using apply the respective settings to the current paragraph. However, the InsertLineBreak() method does not break the paragraph - it only breaks the line. To achieve the desired result you can insert a new line instead:
Additionally, as of next week's LIB two new methods will be included - InsertParagraph() which would break the paragraph and InsertLine(string text) which would insert the string and break the paragraph after it.
I hope this helps.
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