I am not sure how this question relates to the topic of this forum thread.
However, if you refer to the lines inside the content area, it is more likely these to be paragraphs (i.e., P tags). Therefore, it is expected to have some additional padding. If you rather need the new line to act as in plain text editor and to add carriage returns instead, set the NewLineMode property to Br. You can also check out this help article—http://www.telerik.com/help/aspnet-ajax/editor-using-newlinebr-property.html
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