It is expected the two blank lines to appear if there are such BR tags in the content.
This two tags - <br></br> are incorrect and being transformed to two proper BR tags. Note that the BR tag should be only self-closing tags.
Could you please provide more details how these tags appear in the content and what the exact steps for their appearance? Can you reproduce this behavior in one of the Telerik online demos
Any further details will be helpful to examine this behavior as locally I am unable to define what exactly is the reason for the behavior encountered on your end.
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